data prior to 1970

Hello, I need to download the ipums data at the state-year level back to 1968. The following link indicates that the data should be available back to 1962 However, when i tried to download it, Alaska in particular is only available back to 1971. Is there a way I can obtain data back to 1968 for every state-year ? Particularly Alaska on its own (not grouped)? In particular i need marriage rates and shares of population by education group by state-year but i thought i could compute such shares from the individual-level data. If you have them already at the state-year level, even better Thank you very much Monica Deza

The unique identification of some specific states is one limitation of the early samples of the CPS. As noted on the Comparability Tab of the STATEFIP variable: “This variable is comparable for 1963-1967 and 1977 onward, years in which each state and the District of Columbia were separately identified. In the remaining years, two or more states share the same code, and these groupings change over time. In 1962, 8 states cannot be separately identified. In 1968-1972, 32 states cannot be separately identified, and in 1973-1976, 38 states cannot be separately identified. In these years, up to 5 states share the same code.”

The reason for these state groupings is confidentiality requirements and a relatively small sample size in the early years of the CPS. In order to preserve confidentiality of respondents, some states with relatively small sample sizes were grouped together.