The Sunspot Observer - Average annual indices of solar activity NGDC - Solar activity in 1991

Statistics of sunspot activity

Solar activity in 1991

Visual indices of solar activity by National Geophysical Data Center

 
Average by
month
I
II
III
IV
V
VI
VII
VIII
IX
X
XI
XII
days
months
N31283130313031313031303130.4230.42
W188.73243.73173.21191.70153.80209.35213.07229.71168.42187.78152.55188.43191.40191.71
Wn61.7770.8839.2484.4874.35104.56109.3693.2060.7376.2253.6150.7473.2573.26
Ws126.95172.85133.97107.2279.45104.79103.71136.51107.69111.5698.95137.68118.15118.44
n8.5411.818.349.518.3510.7111.4912.478.678.738.358.259.599.60
A1.221.591.351.520.921.671.451.221.241.361.551.141.351.35
B1.451.591.172.281.731.381.351.131.381.541.580.891.451.46
C1.582.621.541.641.862.502.653.221.401.391.241.471.921.93
D1.642.631.401.571.262.192.862.442.091.682.181.981.991.99
E0.350.560.270.540.540.590.420.680.450.540.300.690.500.49
F0.350.360.860.070.020.290.160.170.180.620.160.530.320.31
G0.930.700.530.830.690.500.630.450.350.740.430.900.640.64
H0.080.040.070.030.080.040.150.140.020.010.060.040.060.06
I0.941.711.161.021.251.551.823.021.550.860.850.601.361.36
x2.673.192.513.802.653.052.802.352.622.903.132.032.802.81
r0.370.500.340.550.530.440.490.420.200.360.350.170.390.39
s1.422.671.761.721.692.332.704.122.681.521.861.222.142.14
a2.313.912.472.502.063.533.683.802.412.542.022.482.812.81
h0.080.060.090.040.140.140.210.270.100.080.060.190.120.12
k1.681.471.170.911.281.211.621.510.661.330.942.151.331.33
x2.243.352.582.582.253.263.424.392.812.232.461.782.782.78
o5.257.044.355.894.855.536.446.604.534.864.764.725.395.40
i0.841.201.120.900.761.421.421.261.191.121.031.391.141.14
c0.220.220.290.140.490.500.220.230.140.530.100.360.280.29
CV141.58173.18128.71117.42126.09156.68180.97190.01119.51141.06116.25171.13146.88146.88
CVn44.7249.8523.1159.3174.3190.77101.6977.6137.1647.8839.4140.1957.2357.17
CVs96.86123.33105.6158.1151.7965.9179.29112.4082.3693.1876.84130.9489.6589.72