"By being first movers in increasing abortion access, the five repeal states revealed their willingness to make abortion available. The states that were forced into legalization by Roe v. Wade may have been less positively disposed towards abortion availability, so even de jure legalization may not have implied a large increase in de facto access. Moreover, the women who wanted abortions most in the non-repeal states may have travelled to the repeal states to obtain them, so that the shift in use of abortion after Roe v. Wade was muted. In fact, this view is supported by the evidence on abortion legalization and birth rates in Levine et al. (1996). Their results for the effect o legalization on birth rates are depicted in Figure 2. This figure graphs the relative birth rates of the repeal and non-repeal states over time. Following legalization of abortion in the repeal states in 1970, birth rates in these states fell precipitously relative to birth rates in other states. There is then a corresponding fall in birth rates in the non-repeal states after 1973, so that by 1976 relative birth rates were once again equalized. However, the “bounceback” is slow, only reducing the gap somewhat by 1974-75. Levine et al. present regression results which support the narrative above: relative birth rates fell precipitously in the repeal states during 1971-73, recovered to some extent by 1974-75, and fully recovered by 1976-80. Overall, abortion legalization appears to be correlated with roughly a 6% decline in relative birth rates, which occurred immediately in the repeal states and more gradually in the non-repeal states."