Cohort	Mean	Std. Deviation	Std. Error Mean	95% Confidence Interval of the Difference		t	df	Sig. (2-tailed)
Cohort	Mean	Std. Deviation	Std. Error Mean	Lower	Upper	t	df	Sig. (2-tailed)
2017	−14.212	13.668	1.474	−17.143	−11.282	−9.643	85	0.0001
2018	−11.337	14.264	2.103	−15.573	−7.101	−5.391	45	0.0001
Total	−13.210	13.892	1.209	−15.602	−10.818	−10.925	131	0.0001