Latest (preliminary) Southern Oscillation Index (SOI) values

Note: Calculated using the 1887-1989 base period. This information is usually updated every weekday at 2:00pm (AEST), public holidays excluded.

Date: 22 May, 2008

Average SOI for last 30 days        :   -1.22
Average SOI for last 90 days        :    6.16
Daily contributor to SOI calculation:  -10.78
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Monthly Average SOI Values

   Feb:   20.99
   Mar:   10.21
   Apr:    4.44