@Matty CALCULATETABLE returns a list of Financeal Level 1, when these values are applied to the filter context they will overwrite the existing filter and you will only get the Total P & L of all those values, so to not overwrite the existing filter and to create an intersection between filter context outside CALCULATE and inside CALCULATE we need to use KEEPFILTERS.
REMOVEFILTERS is used so that at each cell of the visual all the Financial Level are visible otherwise TOPN will only receive 1 row containing the value visible in the current cell of the report.
Regarding the above requirement, I see you are using different columns so the granularity is also different, try to adjust the formula accordingly.