. Author manuscript; available in PMC: 2015 Feb 3.

Published in final edited form as: Dev Psychol. 2014 Sep 15;50(11):2449–2461. doi: 10.1037/a0037856

Table 1.

Gender Composition of Peer Groups by Assessment Wave

Gender Composition (% Female)	Fall 6^th	Spring 6^th	Spring 7^th	Spring 8^th	Spring 9^th
All girls 100%	0.40 329	0.39 318	0.33 271	0.28 257	0.25 228
Mostly girls (80–99%)	0.08 69	0.09 78	0.13 105	0.16 140	0.17 151
“Mixed-sex” (21–79%)	0.10 83	0.11 89	0.13 105	0.17 153	0.22 201
Mostly boys (1–20%)	0.06 45	0.06 48	0.06 52	0.07 67	0.10 89
All boys 0%	0.36 292	0.35 292	0.35 293	0.32 285	0.26 230

Total	1.00 818	1.00 825	1.00 826	1.00 902	1.00 899

Note. N of participants included in these frequencies = 14,012.