$500 I Bond with 0.10% Fixed Rate Purchased December 2017

 Infla
tion
Rate
Com
posite
Rate
Jan
1
Feb
1
Mar
1
Apr
1
May
1
Jun
1
Infla
tion
Rate
Com
posite
Rate
Jul
1
Aug
1
Sep
1
Oct
1
Nov
1
Dec
1
2017 500.002017
20181.24%2.58%501.00502.20503.20504.20505.40506.401.11%2.32%507.40508.40509.40510.40511.20512.202018
20191.16%2.42%513.20514.20515.20516.40517.40518.400.70%1.50%519.00519.60520.40521.00521.60522.202019
20201.01%2.12%523.20524.00525.00525.80526.80527.800.53%1.16%528.40528.80529.40529.80530.40530.802020
20210.84%1.78%531.60532.40533.20534.00534.80535.601.77%3.64%537.20538.80540.40542.00543.80545.402021
20223.56%7.22%548.60551.80555.20558.40561.80565.004.81%9.72%569.40574.00578.60583.20587.80592.402022
20233.24%6.58%595.60598.80602.00605.40608.60611.801.69%3.48%613.60615.40617.00618.80620.60622.402023
20241.97%4.04%624.40626.60628.60630.80632.80635.001.48%3.06%636.60638.20639.80641.40643.00644.802024
20250.95%2.00%645.80647.00648.00649.00650.20651.201.43%2.96%652.80654.40656.00657.60659.20660.802025
20261.56%3.22%662.60664.40666.00667.80669.60671.40

From $500.00 to $671.40 over 8.5 years = 3.50% average annual increase compounded semi-annually.

Generated  11/04/25  09:11