The manipulation code appears on row 2 directly under the series ID in column 1 for that particular data series.

By default data is downloaded "in levels" (without manipulation).

Manipulation means you can manipulate the data in several predefined ways. The codes (in parenthesis) and its' respective formulas:
  • Levels (lin): xt
  • Change (chg): xt - xt-1
  • Change from Year Ago (ch1): xt - xt-n
  • Percent Change (pch): ((xt/xt-1) - 1) * 100
  • Percent Change from Year Ago (pc1): ((xt/xt-n) - 1) * 100
  • Compound Annual Rate of Change (pca): (((xt/xt-1)) n – 1) * 100
  • Continuously Compounded Rate of Change (cch): (ln(xt) – ln(xt-1)) * 100
  • Continuously Compounded Annual Rate of Change (cca): ((ln(xt) – ln(xt-1)) * 100) * n
  • Natural Log (log): ln(xt)
...where xt is the value of the FRED series x at time t and n is the number of observations per calendar year. For example n = 12 for monthly data and n = 4 for quarterly data. 

The easiest way to apply manipulation is to first download a series' then replace lin in the cell on row 2 with the desired manipulation code (i.e., chg) then update the data by selecting the following from the Google Sheets menu:

Add-ons>>Federal Reserve Economic Data>>Download All Series

You can also enter the desired manipulation code in the spreadsheet before you download the data.

Update Select Series

Another way to change the manipulation code is to use the Update Select Series feature.

Add-ons>>Federal Reserve Economic Data>>Update Select Series

When you first open the Update Select Series screen, click the box next to the series you want to update. Clicking the Modify download options button at the bottom will take you to the options screen.  

Update Select Series - first screen

Choose the desired manipulation code from the drop down list as shown below.  All series selected in the prior screen will update with the code selected.  

Screen shot - manipulation