Long commute travel to work, dilapidation, abandonment

[MithSimCity]

Hi, I post here because I have never been able to solve the problem of abandonment. I like to make 'planified' cities so I will show a region I made to test this. I used the superdemand mod using only to max the demand for R$$$ (since I suspect they are the more sensible to what I want to test: commute distance), CO$$$ and HT industry, the NAM (version 29 with Z ultra) and some plugins -I can detail them if its needed to solve the problem-

Here's the region:



The transport view:


Here is the city 'Ucronia', as well as in the other one I made two highways crossing in downtown and two diagonal highways -Something like 'Metropolis' city of Simcity 3000 which those nostalgic may remember  -. I also plopped at the beginning the bank of simcity plaza which offers 7000+ jobs:



Here is one of the problems: many buildings abandoned and others dilapidated and the 'no-job' label



Even though I have many offices, even one hurt enterprises tower:



Another thing that puzzles me is the office of the evil dr vu being abandoned due to commute time  (shouldn't be abandoned due to not having clients? -which is not the case since the report shows 'elevated' in clients-) Maybe it's the medium polluted air?



Moreover I checked the travels of the workers to that office and it said that commute time was 'short'



Anyway here is the census report:



----------------------------------------------------------------------------------------------------------------------

I went on to make another city, now without plopping the bank of simcity plaza since I read it could bring problems .

Before that I made a high tech industrial city, here the census info:



So, continuing with the other city, same design than the other -actually I copy the other city to a new region and then imported from there-:



And again the same: abandoned and dilapidated R$$$ buildings due to 'long commute time'. One thing to note is that when there were low density buildings in the same area of the city they reported 'short commute time' (do the sims take much time to take the elevator or stairs?    )





What is strange to me is that they have offices nearby, and all the other needs high:



And a good transport infrastructure to arrive to their jobs:

Monorail:



Metro (I made it like a spider web):



So I don't understand why do they report high commute times with all these means of transport.

It also appeared the problem with commercial offices abandoning due to 'commute time':



By the way, in the previous picture I noticed that CO buildings can face a highway. That's quite unrealistic in my opinion since people can't stop in highways to buy things, well now that I think they could in the stop areas but they are few.

Finally,here is the census report:



I would highly appreciate if anyone could help me to interpret the data from the census report as well as to evacuate these doubts related with this issue and the NAM:

1) I read in a thread that commute time when a sim go to work in another city is long always. How is that? Is there anything to do with the NAM to fix that? I don't see the point of making bedroom cities if so.

2) I also noticed that the airport usage in the cities dropped to zero. Does this effect the game or is just a bug that effects only the display of the travels?

3) Well this third point is actually to summarize what I exposed with the pictures. Basically both cities go through cycles of abandonement and dilapidation and then new buildings are built over the abandoned ones and then the cycle starts again...

(4) Another thing that I noticed is NO crime  in both cities. Maybe it's because of a police station I downloaded here but I will study that in deep later after solving the abandonement issue.

Thanks for your help!!

[Korot]

Another thing that puzzles me is the office of the evil dr vu being abandoned due to commute time  (shouldn't be abandoned due to not having clients? -which is not the case since the report shows 'elevated' in clients-) Maybe it's the medium polluted air?

Clients are based on the number of passing Cars, which seems to be high enough. Don't know for sure about the commute time, but this one also seems to be used when other reasons do not apply, which was due to broken Traffic Sims. The one you use though, doesn't have this problem, but I think my previous sentence still applies, about the commute time reason being used for other cases.

I would highly appreciate if anyone could help me to interpret the data from the census report as well as to evacuate these doubts related with this issue and the NAM:

1) I read in a thread that commute time when a sim go to work in another city is long always. How is that? Is there anything to do with the NAM to fix that? I don't see the point of making bedroom cities if so.

Has to do with the simulator dumping the sim in the middle of the neighbouring city commute wise. Can't be fixed as far as I know, but making bedroom cities should work regardless.

2) I also noticed that the airport usage in the cities dropped to zero. Does this effect the game or is just a bug that effects only the display of the travels?

Hapens to me from time to time as well, but fixes it self quite quickly most of the times, and at other times I simply have to reload the city (Save + exit to region -> reopen city).

3) Well this third point is actually to summarize what I exposed with the pictures. Basically both cities go through cycles of abandonement and dilapidation and then new buildings are built over the abandoned ones and then the cycle starts again...

Look at your Cenus: All your sims are R$$$, all your jobs CO$$$ and I-HT.
Also look at the column labelled drives, which says how much sims of a type you city can support. As you can see, your cities simply don't support your amount of R$$$ sims, or CO$$$ and I-HT jobs. This is because R$$$ don't want to work only at CO$$$ and I-HT, and these types of buildings also employ other workers then R$$$, and that's where things go wrong.

Thanks for your help!!

You're welcome!

Regards,
Korot

[MithSimCity]

Another thing that puzzles me is the office of the evil dr vu being abandoned due to commute time  (shouldn't be abandoned due to not having clients? -which is not the case since the report shows 'elevated' in clients-) Maybe it's the medium polluted air?

Clients are based on the number of passing Cars, which seems to be high enough. Don't know for sure about the commute time, but this one also seems to be used when other reasons do not apply, which was due to broken Traffic Sims. The one you use though, doesn't have this problem, but I think my previous sentence still applies, about the commute time reason being used for other cases.

Well that bug troubles me a lot as it makes me try to fix a problem that doesn't exist and ignore the real one 

I would highly appreciate if anyone could help me to interpret the data from the census report as well as to evacuate these doubts related with this issue and the NAM:

1) I read in a thread that commute time when a sim go to work in another city is long always. How is that? Is there anything to do with the NAM to fix that? I don't see the point of making bedroom cities if so.

Has to do with the simulator dumping the sim in the middle of the neighbouring city commute wise. Can't be fixed as far as I know, but making bedroom cities should work regardless.

Do you mean that the sim starts at the middle of the city border with the city that he/she came? Even though he/she had crossed the border at a corner? If so, although I make many connections in city 1 to city 2, wouldn't all the traffic in city 2 be congested in connection in the middle of the city?

3) Well this third point is actually to summarize what I exposed with the pictures. Basically both cities go through cycles of abandonement and dilapidation and then new buildings are built over the abandoned ones and then the cycle starts again...

Look at your Cenus: All your sims are R$$$, all your jobs CO$$$ and I-HT.
Also look at the column labelled drives, which says how much sims of a type you city can support. As you can see, your cities simply don't support your amount of R$$$ sims, or CO$$$ and I-HT jobs. This is because R$$$ don't want to work only at CO$$$ and I-HT, and these types of buildings also employ other workers then R$$$, and that's where things go wrong.

I see, but there some things that I don't understand/agree:

In 'Ucronia' this is the census:



-The CAP for R$$$ is at 68% so that means that there's still room for growth doesn't?
-The residential capacity is 156,941 but the population is 176,576 inhabitants. Does that mean that there are more inhabitants than the CAP that would allow for them to be there? If so It seems to contradict in my opinion that the CAP for R$$$ is at 68% (it should be at 100% or more, shouldn't?)
-The Total workforce is 80,244 but there are drives for 182,235, and demand for 18,000.
  -What's the diference between drives and demand? I thought they were synonims from what I understood from Demand Simulator: Demand, Supply and CAPs

  -Why is there a demand for 18,000 'workforce' when the demand for R$$$ is 6,000? I mean, shouldn't be more demand for residents than for      workforce? Or maybe this is caused by the superdemand mod that max the demand to 6,000.

-The quotient total worforce/population is 0,45 that is 45% is active population. That is bad from what I remember from my geography teacher  and simcity 3000 . Does it have any effect on the game?

- 'Available vacant jobs: 101,990' : At first I thought 'why do I have unemployment if there are vacant jobs? But after reading  Workforce and Occupation Demands (Drives) I find that from the 173,900 CO$$$ jobs there are, only 26,085 (15%) goes to R$$$


Now the analysis of the other city:



I won't repeat the doubts with the previous city, just add these two:

- 'Available vacant jobs: -21,876' . What does it mean that the number is negative?
- In both cities I observed that commercial and industrial commuters to simnation are 0 when I know because of the 'route assistant' that there are sims that work in the industrial HT city. How's that?

Again, thanks for your help!

PS: Meanwhile I will test two things:
1) Put more CO$$$ zones to see if that ends the problem of unemployed R$$$
2) Put R$$ and R$ sims in the city to see if that solves the problem of abandonment as they will replace abandoned R$$$ buildings. Maybe the problem of abandonment due to commute time is reported as Korot said when there are actually other problems like in this case a lack of employment for R$$$ or a lack of R$$ and R$ workers as you would like to see. But I recall than in cities with all kind of residents, R$$$ would also report long travel commute times. I will test it anyways. 

[HappyDays]

The cause and solution is thankfully fairly simple...

R$$$ Drives: 16,289

This is how many R$$$ the city itself can support. IE, this is the number of jobs available to your R$$$ sims as determined by the capacities of the workplaces in the city.

R$$$: 156,110

This is how many R$$$ you actually have. You don't have enough workplaces for the sims inhabiting the city. Make more workplaces for them in the city or a neighboring city and this problem will slowly fix itself.

As to your other queries:

"-The CAP for R$$$ is at 68% so that means that there's still room for growth doesn't?"

It means your cap is at 68%. Cap is determined by various buildings, such as parks, stadiums, and rewards. It determines how many of a given occupancy group you can have. IE, a cap of 1000 for R$$$ will allow 1000 R$$$ to move in before demand for them literally becomes 0 or negative. It is completely separate from demand. Cap does not generate demand, demand does not change the cap.

As to the question: Yes, it technically means you can stuff in more R$$$. However, as you've seen, this is a bad idea as they'll eventually abandon because they don't have enough jobs to support them.

"-The residential capacity is 156,941 but the population is 176,576 inhabitants. Does that mean that there are more inhabitants than the CAP that would allow for them to be there? If so It seems to contradict in my opinion that the CAP for R$$$ is at 68% (it should be at 100% or more, shouldn't?)"

Your Available Vacant Housing is -19,635, meaning that those extra sims are being added to your population numbers. This shouldn't be possible. This number refers to the amount of capacity in a building that is not filled. Your number indicates far more people live inside a building than its maximum capacity allows.

This tells me something is horribly wrong, but what it is, I do not know.

"-The Total workforce is 80,244 but there are drives for 182,235, and demand for 18,000."

Of your R$$$ sims, 80,244 of them work. The 182,235 drive number indicates that's the total number of working sims your city can support (R$, R$$, and R$$$). Demand is explained in more detail in this topic:

http://sc4devotion.com/forums/index.php?topic=963.0

The 18,000 demand number is ALL of your residential/commercial/industrial demand combined.

[Korot]

Note: Post has been written before HappyDays' post, so we might answer the same things.

I would highly appreciate if anyone could help me to interpret the data from the census report as well as to evacuate these doubts related with this issue and the NAM:

1) I read in a thread that commute time when a sim go to work in another city is long always. How is that? Is there anything to do with the NAM to fix that? I don't see the point of making bedroom cities if so.

Has to do with the simulator dumping the sim in the middle of the neighbouring city commute wise. Can't be fixed as far as I know, but making bedroom cities should work regardless.

Do you mean that the sim starts at the middle of the city border with the city that he/she came? Even though he/she had crossed the border at a corner? If so, although I make many connections in city 1 to city 2, wouldn't all the traffic in city 2 be congested in connection in the middle of the city?

Let's explain this a bit better, shall we?
Let's assume a sim travels from city 1 to city 2.
When calculating a route to city 2, the game looks for the closest neighbour connection (or at least the one that is fastest to reach), and that is where the sims is sent to by the traffic simulator.
However, the job our sim has in city 2 doesn't have to be right near the cities edge, in fact it could be at the other side of it!
Thus, to calculate commute time, the game has to know how far the sim has to travel into city 2 to reach his job. So how could the game do that? Well, the most precise answer is to actually give the sim a job in city 2, and calculate its route in city 2. But, in order to do so, the game has to load city 2. And it has to do that for every sim. And since sims can actually cross entire tiles to find work (go from city A through city B to their job in city C), this would mean that the game has to calculate traffic for your entire region! Imagine what a big load that is on your pc! Now, modern PCs might just handle it, but those from 7 years ago certainly couldn't. So, the game has to take another approach. And that's why the game assumes that the job of our sim is halfway into city 2, ergo: our sim has to travel halfway into city 2 to reach his job.

So how does it calculate commute time? Well, the part in city 1 can be done with actual data: the route is known, and so is the congestion along this route. The part in city 2 has to be guesstimated: halfway into the neighbouring tile on the method of transport used when crossing the border.

And that concludes city 1. City 2 is a bit different, for starters, the sims can enter city 2 using a different neighbour connection, than they used to exit city 1. Example: I had several sims crossing a border by rail, without there being a passenger station on the other side. And indeed, rail wasn't used in the neighbouring city, the sims came in by car. This makes route calculating a bit different as well.
It goes as follows: just like the starting point for our sims journey in city 1 was his house, in city 2 it is the border separating city 1 and 2. Thus, the sim can enter city 2 by any neighbour connection, and will do so on the one that leads him to his job in city 2 fastest. If this job is in city 3, which is just around the corner*, then the sim will enter city 2 through a connection near the edge closest to city 3. If the job is in the centre of city 2, chances are the sim will enter using a connection somewhere in the middle of the border between city 1 and 2.

*) Assume the cities are laid out as follows:
3
2 1

3) Well this third point is actually to summarize what I exposed with the pictures. Basically both cities go through cycles of abandonement and dilapidation and then new buildings are built over the abandoned ones and then the cycle starts again...

Look at your Cenus: All your sims are R$$$, all your jobs CO$$$ and I-HT.
Also look at the column labelled drives, which says how much sims of a type you city can support. As you can see, your cities simply don't support your amount of R$$$ sims, or CO$$$ and I-HT jobs. This is because R$$$ don't want to work only at CO$$$ and I-HT, and these types of buildings also employ other workers then R$$$, and that's where things go wrong.

I see, but there some things that I don't understand/agree:

In 'Ucronia' this is the census:



-The CAP for R$$$ is at 68% so that means that there's still room for growth doesn't?

Yes, it means that you have only reached 68% of the maximal RES capacity.

-The residential capacity is 156,941 but the population is 176,576 inhabitants. Does that mean that there are more inhabitants than the CAP that would allow for them to be there? If so It seems to contradict in my opinion that the CAP for R$$$ is at 68% (it should be at 100% or more, shouldn't?)

Ah, there's your problem! (well, part of it ) You misunderstood the definition of CAP. CAP is not short for capacity. It is simply a cap on your residential growth, and unless raised, your residential capcity can not exceed this level.

Your Available Vacant Housing is -19,635, meaning that those extra sims are being added to your population numbers. This shouldn't be possible. This number refers to the amount of capacity in a building that is not filled. Your number indicates far more people live inside a building than its maximum capacity allows.

This tells me something is horribly wrong, but what it is, I do not know.

Added HappyDays post to answer to his answer as well as your question

And about the discrepancy: read the first lines of you census. Your population is counted on the 12th, while the capacity is counted on the 28th. Thus, on the 12th of June, you had a population of 176,576 and a capacity to support it, but on the 28th of June, you capacity has dropped to just 156,941, probably due to abandonment. If you wait 'till the 15th of July, when the new Population numbers are filed, you will see a drop in population as well.

This is also nicely explained when you mouse over this 'Available Vacant Housing' number: a text will appear saying that this number is only valid the first half of the month, and explain that negative numbers may be due to large buildings being redeveloped.

So no, HappyDays, there isn't anything horribly wrong here, fortunately.

-The Total workforce is 80,244 but there are drives for 182,235, and demand for 18,000.
  -What's the diference between drives and demand? I thought they were synonims from what I understood from Demand Simulator: Demand, Supply and CAPs

Yeah, that might be a bit confusing. If you'd hover over a number in the column drives, you would see exactly what it means: The amount of citizens the current capacity of COM and IND your city currently can support. So if the R$$$ drives are 15,000 it simply means that your city doesn't have jobs for any more than 15,000 R$$$ residents.
The demand is simply how high a demand there is for a certain RCI-type. So a high demand for R$$$ means there is a high demand for R$$$ homes. This does not necessarily mean that there are jobs for these R$$$ sims, though it does have an influence on it, as do education levels and the availability of health-care.

  -Why is there a demand for 18,000 'workforce' when the demand for R$$$ is 6,000? I mean, shouldn't be more demand for residents than for      workforce? Or maybe this is caused by the superdemand mod that max the demand to 6,000.

The max demand for any RCI-type in RushHour/Deluxe SC4 is 6000, which is why your R$$$ demand is 6000. But, the total demand for residentials/commercials and/or industrials can be 18,000. This is because the demand for one group of RCI (RES, COM or IND) is the combined demand of the individual wealth levels and 3 x 6000 is 18000. I think RippleJet can explain this a bit better than I can.

-The quotient total worforce/population is 0,45 that is 45% is active population. That is bad from what I remember from my geography teacher  and simcity 3000 . Does it have any effect on the game?

It doesn't effect the game as far as I know, it's more a consequence thereof. Been a long time since I had geography, but I think this is how the game handles it: Not everybody in the population can be part of the workforce. Children, pensioner and the disabled are part of the population, but aren't part of the workforce. Increasing your healthcare can increase the ratio, as it would decrease the amount of disabled and would allow pensinoers to have a longer, active live span.

- 'Available vacant jobs: 101,990' : At first I thought 'why do I have unemployment if there are vacant jobs? But after reading  Workforce and Occupation Demands (Drives) I find that from the 173,900 CO$$$ jobs there are, only 26,085 (15%) goes to R$$$

Indeed is that why you have unemployment, as far as I know that is.

Now the analysis of the other city:



I won't repeat the doubts with the previous city, just add these two:

- 'Available vacant jobs: -21,876' . What does it mean that the number is negative?

Can you guess it already?  Mouse-over and it will read somewhere that negative numbers indicate unemployment.

- In both cities I observed that commercial and industrial commuters to simnation are 0 when I know because of the 'route assistant' that there are sims that work in the industrial HT city. How's that?

I once had a theory about it, but Tage shot it down pretty much. Problem came up during testing CAM 2.0, which is in a private board, so I'll just quote the relevant bits:

City C has positive residential demand, which is extrapolated to city B. City A has a negative residential demand, which is also extrapolated to city B. The demands of A and C are equal to each other, that is: the net effect of these extrapolated demands on city B are zero.

The CRF shows total, global extrapolation, while the traffic simulator responds to local extrapolation (i.e., from each city).  So it seems that you could get situations like this, at least theoretically.

Not quite... and Carl is showing this perfectly in his post following yours, Steve.
What city B sees are the extrapolated capacities from cities A and C:

• an extrapolated residential capacity of 133 from city A (Commuters from SimNation)
• an extrapolated industrial capacity of 456 from city C (Industrial Commuters to SimNation)

Extrapolated capacity is never negative, and thus they would never eradicate each other...

and

And what about negative demand? Shouldn't that be extrapolated some way as well?

Nope...
It isn't demand that's extrapolated, it's surplus capacity.



First, let's assume a city has too many residents, i.e. there aren't jobs enough for every worker.
In that case there's a negative demand for residents...

However, this is extrapolated to the neighbouring region as surplus (positive) residential capacity
(the Census Repository shows this as residents commuting elsewhere for jobs).

The surrounding cities will see this extrapolated residential capacity,
and the demand for commercials and industrials there will be raised.



Secondly, let's assume a city has too few residents...
In that case there's a positive demand for residents (come and take the available jobs in the city).

However,unless new residential houses are allowed to grow within the city,
this is extrapolated to the neighbouring region as surplus (positive) commercial and industrial capacity
(the Census Repository shows this as commercial and industrial commuters coming from elsewhere to work here).

The surrounding cities will see this extrapolated commercial and industrial capacity,
and thus the demand for residentials there will be raised.



There's never any extrapolation of "negative surplus" (insufficient) capacity...

So the answer is: I have no idea. 

PS: Meanwhile I will test two things:
1) Put more CO$$$ zones to see if that ends the problem of unemployed R$$$

I have my doubts about it, but we'll see.

2) Put R$$ and R$ sims in the city to see if that solves the problem of abandonment as they will replace abandoned R$$$ buildings. Maybe the problem of abandonment due to commute time is reported as Korot said when there are actually other problems like in this case a lack of employment for R$$$ or a lack of R$$ and R$ workers as you would like to see. But I recall than in cities with all kind of residents, R$$$ would also report long travel commute times. I will test it anyways.

R$$$ are picky like that. Doesn't take much for them do describe a commute time as long for them. But yeah, I think allowing R$ and R$$ to settle will solve your problems. At least, most of them.

Again, thanks for your help!

And again, no problem! 

Regards,
Korot

[HappyDays]

"So no, HappyDays, there isn't anything horribly wrong here, fortunately."

Thank goodness!

As for commuters:

Communters to/from SimNation refers to POTENTIAL commuters to/from SimNation. It means nothing more than that. It does not positively or negatively effect gameplay.

My city of 12 million, at one point, had negative 2 million jobs and there were no problems with generating demand or sims as the ACTUAL number of jobs in the city was at a surplus.

[jmyers2043]

EQ is a factor too. Sims will want to work at CO$$$ when they have a high EQ. Sims will generally want to work at I-D or IM or CS$ when they have low EQ.

The thing I don't know is what the super demand mod does. But it appears that with a city EQ of 106 you have the following drives.

CO$$ is 34,915
CO$$$ is 43,011
CS$ is nearly zero at 284
CS$$ is 15,083
CS$$$ is 21,866

Industry does not seem to be a problem as you have about the same number of I-HT drive (job seekers) for the number of jobs available - 8,335/10,404.

But your city is very heavy with CO$$$ jobs at 171,713 and virtually no CO$$, CS$$, and CS$$$ jobs. Just doing some math in my head it seems that about 65% of your Sims want to work at a CO job. The other 35% wish to work at a CS job. Of the CO job seekers I estimate that 60% want CO$$$ and the other 40% prefer to work at a CO$$.

I think that I would try to get a better balance of jobs if that were my city. I don't know why you have so many CO$$$? Perhaps a function of the superdemand mod? Perhaps there are too many parks or landmark lots?

I've never used the mod so this is just speculation. But there is definitely a lack of balance going on. You don't have enough job variety to keep all your Sims happy and employed. That's my best guess.

Good Luck

- Jim

[z]

And that's why the game assumes that the job of our sim is halfway into city 2, ergo: our sim has to travel halfway into city 2 to reach his job.

So how does it calculate commute time? Well, the part in city 1 can be done with actual data: the route is known, and so is the congestion along this route. The part in city 2 has to be guesstimated: halfway into the neighbouring tile on the method of transport used when crossing the border.

And that concludes city 1. City 2 is a bit different, for starters, the sims can enter city 2 using a different neighbour connection, than they used to exit city 1.

This is not quite correct.  Experiments have shown that short, medium, and long commutes are all a fraction of the maximum commute time:  Short commutes are commutes up to one third this maximum, medium commutes are between one third and two thirds of this maximum, and long commutes are anything over two thirds of this maximum.

For reasons explained in A Guide to the Operation of the Traffic Simulator, the maximum commute time in the NAM traffic simulator is 10 hours - 100 times what it is in the original Maxis simulator.  This is necessary for reasons other than commute time; again, see the above reference.  But it means that all commutes within a single city are "short".  All commutes that cross a city boundary are "long".  The traffic simulator does not assume that a commute that crosses city boundaries goes to the center of the neighboring city; that would not produce even a medium commute, much less a long one.  Instead, it just picks a number that is in the range of the long commute and assigns it to that route.  With the NAM traffic simulator, that number is often big enough to take the Sim right off the region map.  This would explain why the commute time graph gets so inflated when you have a large number of intercity commuters.

Failed commutes (due to lack of jobs, etc.) are considered by the game just to be long commutes that exceeded the maximum commute time.  All commutes, whether successful or not, get a commute time assigned to them.

There are no medium commutes when using the NAM traffic simulator.  You might occasionally see Medium as a commute length when you query a residence if the Sims living there have a mixture of long and short commutes; the long commutes may either be to another city, or they may be failed commutes.  The query averages the commute times together.

Short commutes increase the desirability of a Sim's residence slightly; long commutes decrease it slightly.  This increase or decrease is generally not enough to be noticeable.  It appears that buildings become abandoned due to commute time based on the ratio of failed commutes to successful commutes.

Commercial buildings rarely become abandoned and dilapidate; the few times I've seen this, it was due to lack of demand, and the game was seriously out of balance.  I've never seen commercial buildings abandon due to commute time.

Finally, the game is designed so that the Sims enter a second city at the same point and using the same travel type as they were when they left the first city.  The game also keeps track of the number of Sims crossing and their wealth and education levels.  I have done many experiments verifying this.  I have seen some isolated cases where border crossings do not go predictably like this, but this appears to be due to a game bug, and these cases are rather rare.

I've never used the mod so this is just speculation. But there is definitely a lack of balance going on. You don't have enough job variety to keep all your Sims happy and employed. That's my best guess.

I'll second that analysis, and add that more residential variety is needed as well in order to keep the businesses running.  I would recommend against using the super demand mod because of this lack of balance.