My city is in a chronic recession

Question

My city is 1500 years old. It has 1.8 million citizen, 800k businesses and a small industry (around 9k). It's a thriving town running on a $4.5 million yearly budget. It's pretty developed; the crime and pollution rates are low, education and health are pretty high and it has a decent infrastructure (buses and rails account for 20% of traffic). The city is connected to many other cities, it outsources industrial jobs, electricity, water and garbage. It has an airport that handles over a million traveler.

Here is how it looks like from the sky. It's pretty crowded:

And this is only a small part of the whole thing.

But there is a problem here: Technically, and from my estimates, my city can handle up to 3 million citizen and 1.5 million businesses. But it's not. However, it has entered in a chronic recession that no stimulus can escape it. My only escape to the decline of the city is to raise taxes which only worsened things.

Taxes for the poor are at 20%, and 8% for the remaining. Businesses have taxes from 8% to 20%; and the small industry is taxed 8%. When I started the city, the taxes were a lot lower, but since the recession hit (at around 2.0 million population); I had the raise taxes to face the budget deficit.

I have tried lowering taxes for the poor which increases their number, and then convert them to medium and rich citizens. It worked for a while and made something similar to a "business cycle". But this plan no longer works. Lowering taxes to 0% for the poor now barely raises their number (though their number doubles, it's still pretty negligible to the rest of the city population - around 200k -)

I have tried taking all taxes to 0; but this only ruined my thousands' year savings. The city couldn't get alive again. There are dozens (and maybe hundreds) of empty business and residential buildings that could handle a couple more millions of population.

Planning new parts, making projects and things doesn't work; The effect is negligible to the whole. I think the solution is an economical reform but SimCity has poor settings in that area.

How can I bring my city out of this recession?

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Update:

Here is an update with more relevant information. (I'm not sure how to get the file of the city, any tips?)

1. Earnings/Expenses: It's clear from the graph, that there was a financial crash followed by a chronic and slow recession. Less earnings, cut expenses. Cut expenses results in less earnings, that evil circle.

2. Demand: All demand is low, except for the industry. There isn't enough place for the industry (which at the time was around 90K, but is now only 9k). In fact, the city rely a lot on its neighbors for the industry. New neighboring cities always have 100% high demand in High-Tech industry and fill any size of land you give.

Answer 1

If all your industry is in neighboring cities, the cause of your problem could be that one of your transit connections got accidentally severed. If residents can no longer get to their workplaces, they'll move out, lowering population and commerce. This could result in the depression you're seeing.

Therefore, the first order of business is to double-check your transit network. Did you accidentally bulldoze a city-to-city connection, or a tiny section of a major transit artery? Check recent construction zones first, then branch outward. Assuming you have the "Rush Hour" expansion, use the "Route Query" tool to make sure that commuters are actually using all the pieces of your transit network. If there are transit lines that are mysteriously under-utilized, make sure there's not a missing connecting piece somewhere in the transit line. Check all your city-to-city connections. Make sure to check the connections from both sides (both cities). Look for the arrow that indicates it's a city-to-city connection. It's surprisingly easy to accidentally cripple your transit network, and not always easy to spot the cause.

If there are no problems with your transit network, then I don't know what might have happened. To be honest, I've never made a city as big as yours, but from my experience dealing with depressions in smaller cities, the best advice I can give you to get out of this depression is always obey the demand graph.

Your city is demanding more high-tech industry. Build it - and make sure that your sims are able to commute to all your existing high-tech industry.

You say that demand is "low" for residential and commercial property. This is false. The demand is wildly negative. Negative demand means your city has more buildings of that type than its present economy can support. In time, if you can provide enough industrial jobs, these buildings may come back into use. However, if your city isn't going to survive that long, then you may need to bulldoze these unused buildings, and rezone with something your city will fully utilize (HT industry, in this case).

Your sims want high-tech industrial jobs - if you provide new HT industry, this will create new jobs. This should hopefully create a ripple effect - new industry provides new jobs, new jobs will provide new residents to fill up the empty residential space, new residents will buy things and boost local commerce. It will take time, but keep building what your city demands, and the economy should improve. Playing with taxes doesn't solve the problem at hand - your city wants more high-tech industrial jobs. Without available jobs, sims will not move back in to fill any of your unoccupied space.

You can certainly try to continue outsourcing industry to surrounding towns, but make sure you've got a good transit network if you're going to do this. If the industry is too far away from your residences, your sims may not want to make the commute all the way out there. A good transit network lowers commute times and allows your sims to travel farther away from home to get to their jobs. Trains and Subways are great for moving large numbers of people long distances.

If you don't want to optimize the transit network to let your sims commute to out-of-town industrial jobs, then you're going to have to get rid of some residential and commercial property, and replace it with industry.

Long story short, build more high-tech industry, make sure your sims are able to commute to your existing high-tech industry, and if you need to, tear down some of your empty buildings to make way for new industry. They'll never elect you sim-president if you can't prove you're a job creator!

Answer 2

Determine the root cause

It's important to inspect your buildings with the query tool on some of the dilapidated or abandoned buildings. Does it indicate not enough demand or does it also indicate abandonment due to commute time?

A lot of the behaviour you're describing can be ascribed to flaws in the default simulation that rear their head for larger cities.

Cycles

A clue is whether or not you have 'cycles' where buildings dilapidate and restore themselves. This points to a 'desirability' problem. Generally, R$$$ high-rises develop in a moderately-attractive area. The surge of people causes traffic to increase, and then commute times as well. Services can't handle and lower in quality. The desirability drops below 50 and buildings start to dilapidate and now house even more R$$ sims. This makes the problem worse and the situation escalates. Now the buildings house a gigantic amount of R$ sims. (Take Ong condos for example, it houses around 5,000 R$$$ sims but around 20,000 R$ sims). At this point we now get a lot of R$ sims. However, in a very wealthy city without I-D, I-M, I-R and with very little CS$, there isn't a lot of work space for all these poor people. So they leave and abandon because of no work. When all the people leave, the area becomes more attractive again and the cycle starts anew.

Of course, this is mathematically a complex dynamic system with chaotic properties so the reality of it is a little more involved. It may be possible to achieve a somewhat stable equilibrium depending on the model's parameters (e.g. a balance of various stages of dilapidation and abandonment that is 'just right' for a neighbourhood where it maintains itself).

The best advice to give here is the same advice when dealing with logistic models and balancing step size: develop slowly. Don't re-zone huge tracts of the city to high density in one go as this can trigger 'chaotic' dynamical systems where you have a self-reinforcing cycle of abandonment that overwhelms other effects. Aim for no more than 10-20% of one neighbourhood at a time. Let the simulation run for a few years until it stabilizes, then continue, and fix problems as they crop up.

If you have an area that is currently in such a cycle and you want to fix it I recommend reducing the density until it stabilizes. First to medium, then maybe even low density. You can start reintroducing higher density after the cycle stops.

Desirability

There's a problem in SC4 where the threshold where buildings actually will 'build' is far lower than the threshold required to 'maintain' their stature when it comes to desirability. R$$$ has quite steep requirements to not dilapidate when it comes to commute time, traffic, crime, land value, and so on (that collectively determine desirability) but will build anywhere. The result is that if left to build naturally most cities will eventually feature a large collection of dilapidated buildings.

This is actually quite realistic if you want your city modelled after a gritty place like (certain parts of) New York, Chicago, or Detroit.

You can check your 'desirability' area view for areas that are not so green. Fix the problem(s) by removing pollution and traffic, and placing public services (parks, police, education, etc.).

You can also check by inspecting a building using the query tool. If a building houses lower wealth sims than it usually does then it has been dilapidated. If it's not completely 'full' of sims (e.g. amount housed < capacity) then it's progressing towards (further) dilapidation. A building will dilapidate once half of it's inhabitants leave, while buildings of the lowest wealth type will abandon. You can also visually see clues things aren't going so well, such as clotheslines appearing in the back yard of a mansion. R$$$ becomes R$$ becomes R$ before abandon. Similar for CS$$$ to CS$. CO$$$ can become CO$$ and then abandons. The industry types abandon straight away (no wealth progression).

The disparity between 'build' desirability and 'maintain' desirability is also fixed by the 'CAM' mod amongst other things. Also see this thread over at SC4Devotion.

The CAM then has the side-effect of making the simulation a bit less chaotic, the effects described in the previous section are less pronounced.

Over-education

If you build a lot of education buildings, the EQ of your citizens will gradiually over time move to 200. A stable population without an influx of new immigrants will slowly become very educated. Over-education occurs when you don't have many low-education workers but a lot of educated workers.

The highly educated don't want to work in I-M, I-D, or I-R at all and wealthy highly educated don't like lower-paying commercial jobs (CS$ for R$$ and CS$$ and CO$$ for R$$$). However the latter do employ higher-wealth sims (a small fraction of who works there is $$$), so not having any residents with lower education will prevent workplaces from finding workers. No one wants to be a janitor, but we still need them.

Taxes too high

If you 'tax away' part of your demand (like you did with I-D or R$) this can cause inherent problems. Most of your region lives in that one city, and you're artificially removing a natural part of its population. A city is a complex interlocking mechanism, and the posh higher-wealth services like CO$$$ indirectly and/or directly depend on more mundane zones like R$ to survive. While you can use taxes to influence demand, I strongly emphasize that moderation is important. Bump up by a few percent or tenths of a percent to modify 'where' (in which city tile) people settle certain businesses but don't try to use taxes to for example 'expel' dirty industry from your region completely. That's generally bad for the economy. This topic over at SC4devotion has some really nice in-depth info on the way the jobs and residences demands interact.

Taxes are a flat 'modifier' on demand. When they are low relative to other cities in the region, demand is 'poached' from these other places to your city and vice versa. In addition, when taxes are 'too high', then demand is reduced in general. The changes are done by modifying those census drive numbers.

By the way, the reason why you can and do get some R$$$ at the start (when the only office/industry is I-D that only employes R$) is that many government buildings employ them, and they also get employed by CS$$ as well as CS$$$. The former is attracted by R$$ customers and the latter by R$$$.

Much like in SC3000, if your city becomes very large, you should lower the taxes. The 'Natural' tax rate starts out at 9% up to about 600,000 inhabitants and then moves down to 4% at 6,000,000 inhabitants in a sort-of-linear fashion (in small 0.1% increments every so many inhabitants).

Eternal Commuters

This problem (depending on your city topology) might be caused by what is the most prominent known bug in Simcity 4: Eternal Commuters. You say you rely on your neighbouring cities for work.

• Do these neighbouring cities have residents?
• Are they interconnected?
• Are they connected to eachother close to the 4 'corners' of their tiles?

If you answered yes to all three questions, you may have eternal commuters. You can also check with the traffic query tool and add up the numbers and get more commuters than you actually have people working. Here's how it works:

1) When a sim decides where to work, they go to the closest unused workspace. 2) All workspaces in another tile are located exactly at the boundary to that tile (e.g. at each of the connection tile(s)).

Now suppose you have sim A going to work from town A. There's no available workspace in town A, so they look at the borders and decide to go to town B. So from the perspective of town A, you get one commuter navigating towards the border to town B.

When you now simulate town B, you get one commuter incoming from town A. They won't go back to town A, but they look for a job in town B. Now suppose that they came in right at the corner. That means the border to town C is actually 'closer by' than your industry zone. Hence, the commuter will go to town C.

And in town C, they discover the same scenario: town 'D' is closer. And in town 'D' they might decide to go to 'B' again via 'A'. At this point you've got a loop; the amount of commuters will keep increasing while you switch cities. It causes exactly the kind of 'recession' you may be experiencing.

If you want further clarification, also see this post on Simtropolis. As explained there, in order to fully prevent this problem, you can design your transport networks as a 'tree'.

Draw a graph with each of your cities as a node. If there's a connection, connect them with a line. If there is any way to draw a route in the resulting picture that starts in any one point and ends in the same point and does not use any line twice (and isn't the trivial 'empty route') then you do not have a 'tree' graph and eternal commuters may occur.

These eternal commuters or 'phantom commuters' as I'd like to call them effectively come from nowhere and take up jobs. Hence you get a never-ending spiral of traffic and infinite industrial demand but far less residential demand.

Demand Caps

There are hard caps to the amount of people and jobs of each wealth type (R$, R$$, CO$$, I-HT, etc.) you can have in your region, determined by a fixed number. These caps can be raised by certain buildings. E.g. airports, seaports, and network connections will raise the CO caps, while parks will raise the R$$$ cap. Have you tried if building say 10 large plazas nets you an extra 90,000 people? (each plaza is worth 9,000) if so, this can be the culprit. Simply build the required buildings.

Also see the relevant Simtropolis forum thread

The 2km/h speed limit

Sims actually travel at 1.2 km/h on roads in cars in simcity 4 (buses go 2 km/h). They walk at 0.2 km/h. This causes with the default setting that you need to build neighbourhoods quite close, as there's a limit of 2.5 hours to commute time, so sims can't travel more than 3 km on road. In actuality if we use the real speeds: 31 km/h for roads, 5km/h for walking, it computes to 6 minutes. Subways run at 6 km/h (commute time) or 150 km/h (real) so can cover up to 15 km (about 2 large tiles diagonally, use manhattan distance).

Congestion worsens these values. Fully congested roads run at only 30% of the speed of free roads, worsening the issues.

In order to resolve these problems and to be able to build large specialized cities I recommend installing the NAM mod. See its documentation. An in-depth analysis of the subject can be found over at sc4devotion. This is quite a technical post, you may wish to read up on wikipedia about the pathfinding used to gain a full understanding.

Answer 3

I have been having the same problem with my city. It is not nearly this close in population, nor in size, but it will not grow.

I figured that you must meet the need of the high tech needs by increasing parks and rec to bring up land value so that high tech can be built.