Number of doppler-data days processed each year from 1987 to 2006
The large format 1024x1024 Na-dopplergrams are completely processed leaving
only a few 1024x1024 K-dopplegrams and 512x512 Na-dopplergrams to be computed.
The lower panel represents the number of days of dopplergrams that have been
archived and are now available for download from Stanford.