Dataset released under the open data policy
Abstract: World Data Center SILSO, Sunspot Index and Long-term Solar Observations , 1 - 12/2015
Note: Monthly predictions of the sunspot number by Standard Curve and Combined methods + Kalman filter optimization
Links: link
The record appears in these collections:
Royal Observatory of Belgium > Solar Physics & Space Weather (SIDC)
Solar-Terrestrial Centre of Excellence
Datasets