I've attached a spreadsheet I put together for refitting the MAF curve after you've applied corrections. If you don't refit the curve you will have a very choppy looking curve especially at the lower frequency ranges. You don't want that.
To use it paste your existing MAF table to the "Current Airflow" row. Then paste your correction percentages into the "Airflow Error" row. This data should come from a corresponding histogram in your scanner tool and be based on fuel trims and/or wideband feedback. The spreadsheet will then apply a 6th order polynomial fit and spit out a new MAF table in the "Calculated Airflow" row. Paste this back into your MAF table in your editor.
None of this is new but I've seen some posts here and there that mean well but really lead to a less than optimal MAF curve.
The MAF data in the spreadsheet is from my 16 SS. You will see the last cell shoot up significantly. This is not an error. GM decided to utilize 99 of the 100 cells to cover the actual operating range of the stock engine. In past applications they would dedicate more of the table to airflow ranges you would never see in stock form. Once you start modifying the engine or add a power adder the frequency axis will need to be changed to allow the additional frequencies to be calibrated correctly. If you log MAF frequency and see it going past 8550 you should adjust the frequency axis.
Hope this helps. I'll update the spreadsheet as I add more things I find need calculations to be done.
E92 Tuning.zip