Not nearly as uncommon as many would believe. Period 1998-2007
Nationalities surrendered
RUS 18
KEN 14
MAR 14
USA 14
ETH 12
FRA 11
CUB 10
GBR 7
UKR 7
BUL 6
Nationalities adopted
FRA 30
USA 15
TUR 15
IRL 13
ESP 13
GBR 11
RUS 8
CAN 8
BIH 8
AUS 8
US representation given up as often as adopted (14 vs 15)
Most common transition: Marocco to France (12)