Table 1.

Box-Jenkins equations for female cohort life expectancy at age 60 for Sweden (1751 through 1919), France (1816 through 1919) and England and Wales (1841 through 1919).

Country	Box-Jenkins Equation
Sweden	$\nabla Z_t=0.0716+\frac{\left(1+0.4908\right)}{\left(1+0.2743B^7\right)\left(1+0.2567B^8\right)}{a}_t$
France	$\nabla Z_t=0.1428+\frac{1}{\left(1-0.3869\mathrm{B}\right)\left(1+0.5362{\mathrm{B}}^{10}\right)}{a}_t$
England and Wales	$\nabla Z_t=0.0899+a_t$