As of 2014, the most valuable pennies are the 1944 steel wheat penny and the 1943 copper wheat penny; each have been known to fetch values up to $1,000,000 in excellent condition. The 1969-S Lincoln cent with a doubled die obverse and an EF-40 rating has an estimated approximate value of $35,000 and the 1970-S small date Lincoln cent with doubled die obverse has sold for as much as $3,000.
A doubled-die penny is one that is struck with a die that has a full or partial double image that is not double-struck. The 1972 Lincoln cent with a doubled die obverse and the 1995 doubled die obverse Lincoln cent are commonly collected double die pennies and are known to be valuable. The 1999 wide "AM" reverse Lincoln cent is collected because the "AM" is separated from the rest of the word "America" by a small gap. Though the error was repeated for three years, the 1999 cent is the rarest. Its estimated value ranges between $5 and $600.
The most sought-after Lincoln wheat pennies, minted from 1909 to 1955, are the 1909-S V.D.B, 1909-S, 1909-S over horizontal, 1914-D, 1917 doubled die obverse, 1922 No "D," 1931-S, 1943 bronze/copper, 1943-D bronze/copper, 1943-S bronze/copper, 1944-D Over S and the 1955/55 doubled die.