No.
Year
Method
Planck’s constant value
Relative uncertainty
Absolute uncertainty
α range
Comparative uncertainty
Ref.
m2∙kg・s−2
m²・kg・s−2
m²・kg・s−2
1
2007
NIST watt balance
6.626068912
0.36
2.38538481
2.3
0.1037
[34]
2
2007
NPL watt balance
6.626071213
2.0
13.2521424
0.5762
[35]
3
2010
CODATA
6.626069573
0.44
2.91547061
0.1268
[19]
4
2011
METAS watt balance
6.626069120
2.9
19.2156004
0.8355
[36]
5
2011
N-Avog
6.626070000
0.30
1.98782102
0.0863
[37]
6
2014
NIST watt balance
6.626069793
0.45
2.98173141
0.1296
[38]
7
2014
NRC watt balance
6.626070341
0.14
0.95415413
0.0415
[39]