New Goals for the DLC

The City Economic Simulation DLC has the following new goals:

Build a New City Goal 
If you start a new game with the Developed City at the Beginning option disabled, you will be given a goal for building a new city as shown in the below screenshot.

Build a New City Goal

City Goal for Reaching a Population Target 

If you start a new game with the Developed City at the Beginning option enabled or you have built a new city in the game, you will be given a goal for reaching a population target, like the following screenshot shows.

Your city will receive cash rewards when the goal is achieved.

City Goal for Reaching a Population Target