d

Years between C to D

(N1)2

Total messages over 0.1 d

(N2)2

Total messages over 0.001 d

f1

Messages per year

f2

Messages per year

4000

≈0

≈0

≈0

≈0

40,000

222

≈0

≈0

≈0

200,000

8.66 × 107

86.6

4,330

0.43

300,000

2.2 × 109

2,200

74,000

7.4

400,000a

2.2 × 1010

22,000

550,000

55

4,000,000

2.2 × 1018

2.2 × 1012

5.5 × 1012

5.5 × 108

40,000,000

2.2 × 1026

2.2 × 1020

5.5 × 1019

5.5 × 1015