What is the most popular adsense format?

There are many gurus in the world who have talked about this topic. However I was not satisfied with only listening to what they had to say. I wanted to find out what are the formats that real bloggers use. What follows is not my view but my findings based on study of usage of adsense by real bloggers. The link to the excel file with the raw data is here.

The most popular adsense format is 468 x 60
Out of the 15000 blogs that I studied around 3000 used adsense. All these blogs had a total of 6272 adsense blocks. The 468 x 60 format was the most frequently used format followed by 160 x 600 format. Surprisingly link units seem to be used by far too less blogs.

Result of my study of most frequently used adsense format

Width Height Number of times used in the blogs % of total%
468 60 1343 21%
160 600 943 15%
336 280 811 13%
728 90 530 8%
120 600 474 8%
300 250 447 7%
468 15 338 5%
728 15 273 4%
250 250 225 4%
200 200 161 3%
160 90 99 2%
234 60 97 2%
120 240 95 2%

How many adsense blocks should you place on the homepage
I was expecting atleast 2 adsense adblocks to be used on the homepage. Surprisingly 955 bloggers have only 1 adsense block on the home page. Another 722 bloggers 2 units of adsense. I am unable to think why so many people are using only 1 or 2 blocks of adsense on their homepage. Any ideas??

P.S: These studies take up way too much of my time. I was just wondering if anyone other than me finds them interesting or useful. Else I shall rather concentrate on technical posts.Will appreciate if you can let me know what you think of the above data in comments section.

P.S to P.S: Let me know if you want me to analyze something else.

Popularity: 1% [?]