http://www.moneychimp.com/calculator/compound_interest_calculator.htm
Confirm not the same, reason is because that one is single premium endowment.
Yearly addition is different from single premium model.
For single premium model, if you hold it for 20 years, the figure will differ a lot for a small change in compound interest.
Yes, 2.3 % SSB after account for expenses in term(50 K protection with CI, 32 years old start age, 20 years leveled fee) = 1.98% to 2% with protection value.
You can see the difference in percentage is pretty big, cannot say negligible.
If SSB were to beat endowment, interest rate needs to be raised till 4+ %, but the problem is endowment invest in long term bonds as well, so if interest rate rises, most likely endowment return will rise together.
It is very difficult for liquid product to beat illiquid product because they already lower the return rate for additional liquidity.
You want to beat endowment, use another illiquid product like CPF life. This one confirm can beat.