Table 2.

Predicted meta-regression outputs.

Analysis group	n*	First year	First year PMOT**	Final year	Final year PMOT**	Overall change	Yearly change	Slope (95% CI)
Full-refined model	229	1984	63.69%	2019	42.35%	−33.51%	−0.96%	−0.610
>10 Stallions	73	1989	71.31%	2018	53.66%	−24.75%	−0.85%	−0.609
Complete dataset	22	2000	92.48%	2018	34.50%	−45.20%	−2.38%	−1.656
Date restricted	203	2000	51.21%	2019	41.99%	−18.00%	−0.95%	−0.486
F-unselected	151	1984	62.68%	2019	39.85%	−36.42%	−1.04%	−0.652
Western	190	1984	62.04%	2019	45.73%	−26.29%	−0.75%	−0.466
Non-western	32	1995	57.01%	2017	50.94%	−10.65%	−0.46%	−0.710

*Number of articles included in each analysis; **predicted from the fitted model.

Full-refined (meta-regression) model; >10 stallions: articles with >10 stallions; complete dataset: studies with complete datasets; date restricted: studies from 2000 to 2019; F-unselected: fertility unselected.