Structure your data better. Your structure is not suitable for efficient formula building.
For example use database format that is no empty columns, no empty rows such as row 46, 81 etc. in 01-02-23-BB, no totals such as 45, 80, header rows such as 47, 82 etc. Then you might be able to use SUMPRODUCT instead of SUMIFS and so not required to open the data files. You might also want to take a look at Power Query.