GNhs_d.txt (drop last column)
Daily group number from the original series by Hoyt & Schatten 1998.
(-1 values indicate "no data")
Col 1: Year
Col 2: Month
Col 3: Day
Col 4: Date in decimal year (middle of month)
Col 5: Group number Gn
Col 6: Standard error Eg
Col 7: Number of observations