This hand-picked triad of popular proof sets boasts exemplary coins with double-struck, deep-sculpted engravings and spectacular mirror fields. Just 2.7 million five-coin sets were issued in 1984; its output was the second lowest of any clad proof set of the 1980s and the lowest since 1974. Proof set mintages began to decline in the final decade of the 20th century — only 2.3 million were produced in 1994 — and with the exception of the millennial issue, no clad collector's set would ever reach over three million units again. The 11-coin 2004 proof set featured two special Lewis & Clark bicentennial nickels in addition to the year's five state quarters, Sacagawea dollar and standard cent, dime and half dollar. All sets are still in original U.S. Mint packaging.