Passage: On 15 September 2008, it was announced that Lufthansa would acquire a 45% stake in Brussels Airlines with an option to acquire the remaining 55% from 2011. As a part of this deal, Brussels Airlines would join Star Alliance. From 26 October 2008, the ICAO code was changed from DAT to BEL.

Question: How much of a stake did Lufthansa acquire?
45%