All the various global reanalysis products have different periods of record and different update frequencies and delays in updating. For example, ERA-Interim starts in 1979 and updates are available once per month with approximately a 3 month lag. NNRP is available starting much earlier and is updated much more frequently (daily) and is therefore available in the time series tool with a lesser lag of about two weeks. 3TIER currently provides data from 1981 onward for ERA-I and NNRP-D.