The U.S. has experienced a series of dramatic shifts in fertility over the last century. After the huge decline in the mid-20th century, birth rates began to rebound in the 1970s, such that the U.S. had an above-replacement total fertility rate of 2.12 children per woman as recently as 2007. Since then, TFRs have declined in ten out of the eleven subsequent years, reaching an all-time low of 1.73 in 2018.