42% by Pius
According to this blog
[http://totuspius.blogspot.com/2006/06/pii-responsible-for-42-of-church.html],
Popes named Pius declared 42% of the Church Doctors.
St. Athanasius (296-373)- Declared Doctor in 1568 by St. Pius V
St. Hilary of Poitiers (315-367)- 1851 by Bl. Pius IX
St. Gregory of Nasianzus (325-389)-