I am not sure if there is anything you can do about this, however you start the game with 15 parsnips in Year 1. This is not accounted for in the planner which in ends up making the profit incorrect as you are -300g for "buying" 15 parsnips you got for free.
I, and most others, can just do the maths in my head to figure what the actual profit will be. But if this can be corrected it will make the planner that much better. Sorry if this was the wrong way to submit this.