In the cities options menu, there are several options for interacting with the particular city. There are several of them, but of importance in this sector, are small, medium and large advertisment. What advertisment does is that it increases a cities rating to all station within range to 100%. But only for that week, then it will slowly go back to normal. However, if one use advertisment once a week, the station will have 100% rating. But first of all, what are the difference between the three ratings?
- Small advertisment reaches 10 tiles from city center.
- Medium advertisment reaches 15 tiles from city center.
- Large advertisment reaches 20 tiles from city center.
Important to remember is that the tiles are calculated using the manhattan distances. Manhattan distance does not calculate diagonally but rather each step.
Then, what are the usage of advertisment?
Lets illustrate it by an example. In your city, there is a factory producing 5 000 goods per month. You use trucks to send this goods into the city. All is fine until your city starts to demand more than 3750 goods. Because your factory has a productivity of 75% (equals to your stations rating) it really just produces 3750 goods/month for you. Now, in this case, your goods loading stations sign is within 20 tiles of the city so it will be effected by the large advertisment option. So, you start, each week, buying a large advertisment, which will knock up your goods per month to 5000. Now you suddenly got 1250 more goods per month and can grow even larger.
Pictures to show it all:
But if we advertis each week, this will happen:
Resulting in twice the amount of goods for the city. Or half the amount of trains required, if one look at it that way.
Another usage of advertisment is using it to store goods for later purpose. This has been used in all games where the pop has been really high. You are building another city, and you build a factory next to it for goods. The trains starts coming in and your factory are producing plenty of goods and all seems well. Except for the fact that your city doesn't need so much goods and there are plenty of goods going to waste. You got the trucks up for goods, but only using a few trucks as you don't need so many yet. With the low amount of trucks therefore little pressure on your factory, the station rating is very low. Also, this game has a decay, that unused goods at a station will disappear if they are not transported, so all in all, you are lossing a lot of goods. If you start using advertisment, you will get a much better rating from the factory and work against the decay. Soon you notices that your station will harbor thousands of goods that can be used when city requires more than you can produce.
There is one last, minor, thing with advertisment. Primary industries do increase or decrease their production, randomly it might seem, but not the case. They are actually effected by the station that transport their goods. That is, the stations rating. Having a station at excellent or outstanding rating will have a much greater chance of increasing that stations production. This is, however, of much bigger impact on ECS servers than on normal servers as it take time. And this is the reason why there sometimes are coal mines with 500-600 coal/month on LS 1 and 2 at the end game.