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5. Averaged LOS velocities are obtained by dividing the sum of the interferograms by the cumulative time of the interferograms since 12 May 2002. The averaged rates cover slightly different time periods since the beginning of the inflation (3.41 3.30 3.37 and 3.26 years for Standard Beams A3 A6 D1 and D6 respectively) but we verified that this does not affect our conclusions. We neglect the subtle deflation of the summit area before May 2002 ( 16 ) which according to 1997 to 2002 InSAR data occurred at a rate below the measurement noise.