Please answer a question about the following article about Party leaders of the United States House of Representatives:

Like the Speaker of the House, the Minority Leaders are typically experienced lawmakers when they win election to this position. When Nancy Pelosi, D-CA, became Minority Leader in the 108th Congress, she had served in the House nearly 20 years and had served as minority whip in the 107th Congress. When her predecessor, Richard Gephardt, D-MO, became minority leader in the 104th House, he had been in the House for almost 20 years, had served as chairman of the Democratic Caucus for four years, had been a 1988 presidential candidate, and had been majority leader from June 1989 until Republicans captured control of the House in the November 1994 elections. Gephardt's predecessor in the minority leadership position was Robert Michel, R-IL, who became GOP Leader in 1981 after spending 24 years in the House. Michel's predecessor, Republican John Rhodes of Arizona, was elected Minority Leader in 1973 after 20 years of House service.

How long had Richard Gephart served in house prior to being elected to minority leader?
20 years