The Interest Rate is the eight upgrade.
| Level | Cost | Effect |
|---|---|---|
| 1 / 10 | 10K / 1e150 | |
| 2 / 20 | 100K / 100e156 | |
| 3 / 30 | 1M / 10e165 | |
| 4 / 40 | 10M / 1e180 | |
| 5 / 50 | 100M / 100e189 | |
| 6 / 60 | 1B / 25e204 | |
| 7 / 70 | 10B / 50e216 | |
| 8 / 80 | 100B / 1e240 | |
| 9 / 90 | 1T / 1e258 | |
|
10 / 1a1 |
10T / 100e276 |
Workshop
Engine & Engine Upgrade • Cogwheel & Big Cogwheel •
Hammer & Hammer Upgrade • Money Machine Upgrade & Interest Rate •
Balloon Pump & Balloon Pump Upgrade & Balloon Speed •
Portal & Portal Amplifier & Charger Upgrade •
Mine • Selling Detail
Clockwork City
House & Tavern & Building Upgrade • Planet & Planet Upgrade •
Tower • Windmill & Bellow & Bellow Upgrade • Propeller •
Tax Collector & Tax Collector Upgrade • Crystal & Crystal Upgrade