Population

Overview
Population and growth: The maximum population of a city depends on the number of Apartment Buildings. The more you build and upgrade these, the higher the pop. cap will be. When the population is below the maximum possible, it will slowly increase until full. You can also work in Apartments to gain people instantly, though this uses up a lot of energy.

Passive population increase starts at 50 per hour. Constructing the Hospital and City Administration buildings will boost the hourly population growth. Your current city population and growth per hour can be checked in the "Your city" menu.

Jobs and unemployment: Every citizen requires a job in your city. Having more jobs than people will leave buildings understaffed and operating inefficienty (e.g. an understaffed hotel will give less profit overnight). But having more people than jobs will increase the unemploment rate, and every one unemployed citizen will take away 50 credits per hour.

You should always aim to have slightly more people than jobs in your city. Most buildings need employees, so focusing on building new Offices will just take away employees from other important buildings. Upgrading a building increases its jobs.