People often forget just how massively popular Chicago were in the 1970s. They released an album every single year that decade and scored huge hits with "Saturday in the Park," "Old Days," "If You Leave Me Now," "Call on Me" and many others. When they launched an arena tour in 1973, Bruce Springsteen was opening for them. The hits continued through the 1980s, but they never quite recovered from singer Peter Cetera's departure in 1985. They've been eligible for the Hall of Fame since 1995, but have yet to appear on a single ballot.