Table 3. Men’s and women’s freestyle swimming events, type of mathematical function and predictive equations.

Gender	Event	Type	Equation	R2 value
Men	50m	Inverse	y = -44.77 + 134064.199 / year	.543 ns
	100m	Compound	y = 42747.22 x .99year	.972 *
	200m	Sigmoidal	y = e- 1.33 + 11971.98 / year	.862 *
	400m	Cubic	y = 12572.6 - 8.79 x year +6.53 x 10-7 x year3	.977 *
	1500m	Cubic	y = 4045.71 - 27.31 x year + 1.88 x 10-6 x year3	.963 *
Women	50m	Inverse	y = 71.68 + 193578 / year	.732 ns
	100m	Cubic	y = 7417.11 - 5.48 x year + 4.5 x 10-7 x year3	.959 *
	200m	Sigmoidal	y = e-0.54 + 8451.02 / year	.812 *
	400m	Cubic	y = 1565 - 1.68 x 10-7 x year3	.976 *
	800m	Sigmoidal	y = e-1.26 + 14938.8 / year	.692 *

ns: due to the small degrees of freedom* p < 0.05