According to ICC recent release of T20 Ranking, Sri Lanka is on the top of the table with 13 matches and 135 ratings while Australia is on the second spot with 16 matches and 122 ratings.
India is on the third position while England on 8th position and Afghanistan being ahead of Bangladesh is on 9th.
Hong Kong with their outstanding performance on ICCT20 Qualifier is at 11 position, while relatively poor performer of ICCT20 Qualifier but strong associate Nation Ireland is on 15th position.UAE and Oman are listed in ICCT20 but due to insufficient matches are not in any ranking.
Nepal who had Qualified for the previous edition of ICCT20 world cup has loose their ranking with insufficient matches and poor performance in ICCT20 Qualifier.
You can find a detail article about the calculation of ranking here