You can change inbuilt html AdSense code in blogger by following the steps given.
1. Login your Adsense account
2. Click on 'My Ads' tab
3. You will be at default 'Ad Units' tab where you can see your blogs name / list with Adv code/size etc. (Active status one).
4. Check the blog and ad which already exist with 'Active' status
5. Click on 'Edit ad type' option, select type and save for which you want it.
6. Click on 'Performance Report' Tab
7. Click on 'Ad Units' option at the left side
8. Once you reach the screen, you may then take mouse/arrow toward lining bar to know each ad type performances.
9. It will show blog/site name, type/size of ad, estimated earnings and clicks for the selected date ranges.
Note: You can select the date above at right side, and the lining bar will only show for selected and performed ad types than poor performance one. Also, this step/procedure may change for new Adsense account enhancement.