Formula needed for irregular rate of return through out any given time frame/year

Im wondering if anyone could provide me with a bit of help for a formula to calculate this here.

lets say i invest 10000 jan 1st
jan 3rd it is worth 10120
jan 8th 10140
jan 10 10200
jan 15 10240

I currently have columns stating the different change in value from jan 1st to jan 3rd, jan 3rd to 8th.
a column showing what the % change is day to day

How do i get a percent earned on each row
so i believe i start with difference / original investment

10120 - 10000 = 120
120/10120 = 0.01186 1.18%

10140-10000=140
140/10140 = 0.01381 1.38%

10200-10000=200
200/10200=0.01961 1.96%

I'm not sure if I'm off track.. but I'm looking for a formula that will calculate my rate of return on each new day i input values. I feel like 1.96% year to date return is not correct? do i need to do something with days in a year and create more columns to figure days remaining or days into the 365.. Very confused please help!!
thanks

You need to divide the percentage you calculated by the number of days elapsed to get the daily rate. You will then need to multiply that by 365 to get the annual rate. your 1.96% is the raw percentage change.

In your example for Jan 15
.01961/15 = .001307
.001307*365=.477177 or 47.72%