Thanks! Great!

I had just been searching under "ClimAdjust", a term in the file you used... and that led me to a [a conversation](;wap2) in which someone said this:

I've been using Mark's marine weather forecasts for over 15 years now I've found them to very accurate & reliable. Nonetheless, I agree that the values cited by Mark are a bit too low but only SLIGHTLY. The historical values of the ONI computed by NOAA's CPC have slightly changed due to an update in climatology (I can't say for sure but I believe this is why the values cited by Mark were low). Below is the monthly Nino 3.4 index for 1997/1998 using the new strategy. For a detailed description of changes to the ONI you can check out the following link.

Monthly NiƱo-3.4 index

1997 1 26.09 26.68 -0.58
1997 2 26.47 26.84 -0.38
1997 3 27.15 27.34 -0.19


I checked and noticed that this data matched "your" file...

This is like detective work.