Hi Jacek,
In CJ30, please use 'copy view' to copy 'cumulative budget' to overall budget.
This will copy total of years budget to overall.
Follow below steps.
1. Go to CJ30
2. Enter Project definition and press enter
3. Go to path Edit-> Select->Select All
4. Again go to path Edit-> Copy view->Cumulative
5. Choose percentage as 100% & overwrite
6. Select OK to save changes.
Regards
Tushar