This is some fantastic information compiled by Macraider on the treasury's ROI.
"I'm working towards T4 and need gold. The Treasury is a welcome addition to the game and upgrading the treasury should in theory greatly increase the benefit the building provides. A better interest rate means more gold, faster.
That got me thinking, if I have to buy War Bonds in order to upgrade this building, how quickly before I earn enough gold back to justify the cost of the War Bonds. (War Bonds cost 20 gold each when purchased individually, or as low as 14 gold when you buy 1,000 for 14,000 gold.)"
The bottom line is upgrading to Lvl 2 is a must do, and Lvl 3 a good idea. But beyond that, unless you are very patient, you might not be happy with the return on your investment (ROI).
*Here's why:
Format: Bonus interest / Cost to buy bonds / Return on Investment time /
*Assumption: Repeated 7 day Certificates of Deposit
Lvl 2: 1% / 5 for 100 gold / approx. 7 days
Lvl 3: 2% /25 for 350 gold / approx. 14 days
Lvl 4: 4% /80 for 1,120 gold / approx. 25 days
Lvl 5: 7% / 295 for 4,130 gold / approx. 67 days
Lvl 6: 15% /900 for 12,600 gold /approx. 95 days
Lvl 7: 20% / 3,500 for 49,000 gold / approx. 50 days
*Some of you are probably like, "Navi why are you saying to do repeated 7 day deposits?!" It's important to understand, the 30 day pays more in gold interest than the 7 day. But for the purposes of calculating ROI, you will get your gold back faster by doing 7 day investments. We are not talking about which investment pays more, we are talking about which investment nets a higher return because of the upgrade. Whether you are at Lvl 3 or Lvl 4, if you are willing to wait 30d for your interest you are going to get a better return. The question was, is Lvl 3 good enough or is Lvl 4 really better (all other things being equal)?
*The cost of resources is not taken into account, because they are relatively easy to acquire.
Thank you Macraider!
Enjoy!
Navi
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