I was playing an island city, and everything was going spectacularily for 50 years. Then, almost in the blink of an eye, my entire economy just crashed.
-I went from +$6,000 a month to -$3,000 a month.
-My demand for everything plummeted. There was negative demand for every class.
-Population went from 147,000 to 105,000 in about 3 months.
- At least 30% of all buildings turned black and mouldy.
I have no idea why this happened. I made a save and tried everything possible. If I raised taxes, the demand just sunk even lower, resulting in even more mouldy buildings. If I lowered taxes, my monthly income went even lower. It's a no-win scenario.
Information about the island.
-131,717 Residential (was 147,000 before the economy collapse)
-58,000 Commercial (Unsure what it was before collapse)
-9,578 Industry ( was 14,000 before collapse)
-The desirability for R$$$, CO$$$, and I-HT is green for almost the entire island (except for the military base and landfill).
-3 Seaports, heavily used.
-Just finished rezoning my entire industry region, and completely removed dirty industry. 90% High-tech, 10% manufacturing.
-Just upgrading my large landing strip to a small municipal airport to accomodate more people (large landing strip was maxed out).
-Large and well-used public transit system. Monorail, bus, subway, and ferry system covers the entire island. Nothing is under-used.
-I had a few ordinances in place. Mostly to improve health care, reduce traffic, and reduce pollution (left over from the dirty industry days).
-$160,555 in bank. Was saving up for a landmark to boost commercial district.
-Power grid is 100% solar power (waiting to unlock nuclear power).
-Many residential skyscrapers. Almost (not quite all) of my residential zoning are skyscrapers.
-Only a few commercial skyscrapers. No stage 8's.
-4 hospitals. 3 of them are about 70% capacity. The middle one is over 100% (can't seem to lower it, no matter how many hospitals I place).
-3 Elementary schools, approx. 60% full each. If I remove one of them, the other two will become maxed out.
-1 High school. It's holding at about 70%.
-1 College. 1 Museum. 3 Libraries.
-EQ is between 160 and 200.
-No University. Technically I unlocked it, but after leaving and coming back, it's returned to locked and I can't unlock it (without cheats).
-Zero Neighbour connections (unless you count seaports and airports.) It's an island, nothing I can do about it.
I'm not really sure what else to add. This is my first successful city, and help would be appreciated! If you need any more information, feel free to ask. How do I return back to my wealthy, successful island?