During April 1999 the Sun had staked 53 geomagnetic quiet (Ap<20 nT) semi diurnal intervals and 7
 stormy ones.
SSM had predicted 49  GQIs and one GSI (April 17, first).
SEC had predicted 40 GQIs and 4 GSIs (April 16, second; April 17, first; April 29, second; April 30, first).
So one can see:
 

Rating list for April 99

Place	GDIs	GSIs	Total
1	SSM : 0.92	SEC : 0.57	SSM : 0.83
2	SEC :0.75	SSM : 0.14	SEC : 0.73