By the 1980s, parents of mixed-race children (and adults of mixed-race ancestry) began to organize and lobby for the ability to show more than one ethnic category on Census and other legal forms. They refused to be put into just one category. When the U.S. government proposed the addition of the category of "bi-racial" or "multiracial" in 1988, the response from the general public was mostly negative. Some African-American organizations and political leaders, such as Senator Diane Watson and Representative Augustus Hawkins, were particularly vocal in their rejection of the category. They feared a loss in political and economic power if African Americans abandoned their one category.

Answer this question, if possible (if impossible, reply "unanswerable"): When did people lobby for allowing more than one category to be selected on legal forms?
the 1980s