I do not have XIRR function to calculate IRR for my investments. I
only deposit, do not withdraw, can someone help me with formula or
installing XIRR.

The formula others use:

([old value-.5* deposits]/[end value+.5*deposits])-1

this worked well when combining 6 accounts (two 401k, 2 Roth IRA, 2
Rollover IRA), = 4.7% IRR, but did not do well with each sub account
(no account had less than a 30% IRR).

suggestions?