Predicted range	Likely usage	Actual patterns	Date(s) used
100-999	all	900	up to and including 1915
1000-1999	all	1000	1916-1920
2000-2999	all	1000	early 1920s
3000-3999	none	none
4000-4999	up to 4745	800	early to mid-1920s
5000-5999	up to 5577	600	1923-1925
6000-6999	up to 6017	20	end 1925/start 1926
7000-7999	all	1000	1926-1928
8000-8999	all	1000	1928-1930
9000-9999	up to 9726	800	1930-1931
A100-A999	all	900	1932
A1000-A1999	all	1000	1933-1935
A2000-A2999	all	1000	1935
A3000-A3999	all	1000	1936
A4000-A4999	all	1000	1937-1938
A5000-A5999	all	1000	1938-1939
A6000-A6999	up to A6018	20	1939
A7000-A7999	all	1000	1939-1945
A8000-A8999	all	1000	1945-1951
A9000-A9999	all	1000	1951-1955
B100-B999	up to B172	100	1950s
D100-D9999	up to D2542	2500	1950s-1962
S100-S9999	from S1400 to S1600	200	1950s
TOTAL PATTERNS		18840