Table 1: There is some evidence that revisions are marginally statistically significant when looking at the final quarterly estimate of GDP
"Revision information and t-test for statistical significance for quarterly GDP growth, UK, Quarter 2 1961 to Quarter 4 2020 "
,T + 3,,,,T + 36,,,
Timespan,"Mean
Revision
(pp)","Absolute
Average
Revision
(pp)","T Score
[note 2]","Statistically
Significant?","Mean
Revision
(pp)","Absolute
Average
Revision
(pp)","T Score
[note 2]","Statistically
Significant?"
"1961 Q2
to 2020
Q4
[note 1]",0.0,0.2,1.9,No,0.1,0.5,2.3,Yes
"1961 Q2
to 1969
Q4
[note 1]",,,,,0.1,0.8,0.4,No
"1970 Q1
to 1979
Q4
[note 1]",,,,,0.3,1.0,1.3,No
"1980 Q1
to
1989 Q4",0.1,0.3,1.6,No,0.2,0.7,1.4,No
"1990 Q1
to
1999 Q4",0.0,0.1,0.4,No,0.1,0.2,2.6,Yes
"2000 Q1
to
2009 Q4",0.0,0.1,0.2,No,0.0,0.3,0.0,No
"2010 Q1
to 2020
Q4
[note 3]",0.1,0.1,1.6,No,0.1,0.2,1.4,No
Source: ,Office for National Statistics
Notes
1,"Because of the compilation process at the time, t plus three months has no revisions pre-1980. "
2,Two tailed standard significance test at 95% confidence interval.
3,"We do not have a t plus 36 months estimate for Quarter 3 (July to Sept) 2020 and Quarter 4 (Oct to Dec) 2020. However, our revisions policy is such that these current estimates will not be revised before we get to the t plus 36 months stage and so this has been inferred for these purposes. These have gone through two supply and use tables (SUTs) balancing processes, which is the basis of the “final” estimate being chosen. "