The graph above shows the total sales, in millions of dollars, for three companies, A & B & C, in a particular sector for the years 1998 through 2007 inclusive. Assume these companies are the only three companies active in this particular sector. Companies A & B existed since the 1980s, although only data from 1998 is shown. Company C's first year in existence was 2000.
Total sales, by all companies in the sector, increased by approximately what percent from 1998 to 2007?
Three Companies in a Sector