I like to take a rule from the Steve jobs playbook and use simple circles... one larger than the other but no more than 2. your most immediate target (realistic reachable) and one of the "enemy" competitor company. or overall untapped market cap.
**for this to be effective you must provide as accurate projections as possible**
no bar graphs and as little or no text as possible... remember that a deck is a companion to the speaker... avoid bullet points and use the deck to entertain rather than educate... is not a class is a pitch. :)