How to fix a slow excel calculation?

[Jisu_Kim]

I made a calculator using excel2013 for analyzing rainfall data.

(input data = white cells, final output data = yellow cells)

But it is too slow for a calculation when i changed the old input data to new input data.

how do i make it better? is there anyone who can help me?

[#2]

@Jisu_Kim 

As a minimum use dynamic ranges in formulas, e.g.

=SMALL(Z1:INDEX(Z:Z, COUNTA(B:B)),AB2)

instead of

=SMALL(Z:Z,AB2)

in all other formulas as well.

[#3]

@Jisu_Kim 

800,000 formulas is a bit to much for any workbook.

You could do all the calculations in Power Query.

[#4]

@Sergei Baklan

Thank you for your reply.