The months in the Islam calendar

I used to wonder, why does the big events in Islam always changes from year to year, once we had a Kongsi Raya, where the Chinese new year and hari raya aidilfitri was together...
Then later hari raya was in July later on hmmm

So a simple extraction from Wikipedia shows us the number of months is shorter than our gregorian calendar. 

No	Penanggalan Islam	Lama Hari
1	Muharram	30
2	Safar	29
3	Rabiul awal	30
4	Rabiul akhir	29
5	Jumadil awal	30
6	Jumadil akhir	29
7	Rajab	30
8	Sya'ban	29
9	Ramadhan	30
10	Syawal	29
11	Dzulkaidah	30
12	Dzulhijjah	29/(30)
Total		354/(355)

So I'll just stop here =) 

Happy awal muharram. 

May our lives be blessed by Allah =)