There seems to be a difference between the available Store Credit of yours with the site currency you had picked previously. Would you like to:
XBOX Live (Microsoft) VideoGame USD $152.16
XBOX Live (Microsoft) VideoGame USD $68.46
XBOX Live (Microsoft) VideoGame USD $54.77
XBOX Live (Microsoft) VideoGame USD $182.6
XBOX Live (Microsoft) VideoGame USD $60.81
XBOX Live (Microsoft) VideoGame USD $54.39
XBOX Live (Microsoft) VideoGame USD $20.69