In 2011, there were 3,640 girls named Morgan and 469 boys (nearly 8:1 in favor of girls).
Morgan is a little bit of an odd case because usually when a name goes over to the girls, it doesn't go back to the boys. That's mostly true with Morgan, but it hit its peak "girl-ness" in the 1990s and has drifted slightly back toward unisex usage recently. It's still used much more frequently for girls, but not quite as overwhelmingly as in the '90s. This makes me think that it is a bit different from names like Ashley that went wholly over to the girls' side.
1965: 44 girls, 208 boys (1:5)
1975: 113 girls, 283 boys (1:2.5)
1985: 2,279 girls, 683 boys (3:1)
1995: 10,876 girls, 1,257 boys (9:1)
2005: 6,743 girls, 900 boys (7.5:1)