Return period (years)

10

20

50

100

500

Return level (s)

10.03

9.86

9.74

9.69

9.62

Standard error

0.0772

0.0638

0.0491

0.0457

0.0568

95% CI

(9.88, 10.18)

(9.74, 9.99)

(9.64, 9.84)

(9.60, 9.78)

(9.51, 9.73)