As players build and improve their villages, they are presented with the Land Annual GDP (gross domestic product).
The Annual GDP represents the annualized value of items produced on your land using real-time market value of those items. It also takes into account the amount of troops the village produces and capacity to produce goods. For example, if you build a blacksmith on your village, the amount of swords the blacksmith is capable of producing daily is factored into your annual GDP.
This is the most accurate representation of how well you are doing in the game at improving your land and monitoring the economy.