Success criteria for OpenTTD

I started playing OpenTTD again after many years and enjoy it a lot just building stuff.

I am just wondering what can be seen as the objectives of the game, besides accumulating money. I also don't play with competitors, so I cannot compare myself to others. Thus I was thinking of some other metrics. E.g. the connectivity of the network, eg. reach a point where a passenger would be able to travel from any city to any other city and what would be the average travel time/distance.

Is there any way to get this or similar success statistics?

Generally, most people like to play OpenTTD as a sandbox game, where the goal to build up complex and efficient transportation system for delivering resources. This basically means you should try to do whatever you want as long as have fun. However, 'officially' the goal of the game is try to reach the maximum possible 'company rating' by the year 2050, where the game would officially end and you would be given a title. Company rating is computed using this formula found on the OpenTTD wiki.