1950-1954 =Up to 6,000
1954-1956 =Up to 10,000 -4 or 5 digits (inc 0 or - prefix)
1955-1956 =10,000 -" " " " " "
1957 = 10,000-20,000 -5 or 6 digits (inc 0 or - prefix)
1958 = 20,000-30,000 -" " " " "
1959 = 30,000-40,000
1960 = 40,000-50,000
1961 = 50.000-70,000
1962 = 60,000-90,000
1963 = 80,000-90,000
1963 = Up to L10,000 L + 5 digits...(beginning of the infamous "L" Series)
1963 = L10,000-L20,000 " "
1964 = L20,000-L50,000 " "
1965 = L50,000-L90,000 " "
1965 = 100,000
1966-1967 =100,000-200,000
1968 = 200,000
1969-1970 =200,000-300,000
1971-1972 =300,000
1973 = 300,000-500,000
1974-1975 =400,000-500,000
1976 = 500,000-700,000
1976 = 76 or S6 + 5 digits
1977 = S7 or S8 + 5 digits
1978 = S7, S8 or S9 + 5 digits
1979 = S9 or E0 + 5 digits
1980-1981 =S9, E0 or E1 + 5 digits
1982 = E1,E2 or E3 + 5 digits
1983 = E2 or E3 + 5 digits
1984 = E3 or E4 + 5 digits
1987 = E4 + 5 digits
1988 = E4 or E8 + 5 digits
1989 = E4 or E8 + 5 digits
1990 = E8 or N9 + 5 digits
1990 = N0 + 5 digits
1991 = N1 + 5/6 digits
1992 = N2 + 5/6 digits