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Around the Internet => Continue the Blog Conversation => Topic started by: Leggo on May 25, 2015, 01:02:12 PM

Title: Growing your kiddo's MM
Post by: Leggo on May 25, 2015, 01:02:12 PM
Loved the article on what you're teaching your son about money.  Thanks for including the example excel spreadsheet.  Any chance you'd be willing to share the formulas you used to populate the cells?  I'm not great with Excel, and apparently, not so great with math, either.  I can get the spreadsheet to calculate monthly interest, but can't figure out how to let it calculate interest based on number of days, as you show in your example.

Any help is appreciated!
Title: Re: Growing your kiddo's MM
Post by: SpeedofTim on May 25, 2015, 04:24:42 PM
Yes please! I was just searching the forums for the same thing.  I know I can recreate a basic deposit entry spreadsheet, but I'm curious as to how the interest calculations are done.

Thanks!
Title: Re: Growing your kiddo's MM
Post by: StockBeard on May 27, 2015, 10:39:02 AM
Also, I'd love to understand how you get a 10% rate for your kid. Doesn't that skew your kid's expectations for what return they'll get in the future?
Title: Re: Growing your kiddo's MM
Post by: CheapskateWife on May 27, 2015, 11:29:40 AM
To the request for an excel document, I put together this quick calculation, and when you plan to add on, you simply copy and paste the last filled line into the first empty line.
Title: Re: Growing your kiddo's MM
Post by: MDM on May 27, 2015, 11:50:32 AM
To the request for an excel document, I put together this quick calculation, and when you plan to add on, you simply copy and paste the last filled line into the first empty line.
Nice!  One might want to use formulas in columns C, D, and E.  E.g., see table below.  Other bells & whistles no doubt possible.

Kid's Bank Account Statement
Interest rate0.1
DateNew ContributionNumber of daysInterestInterest EarnedTotalComment
4214430 =E6+B6Imported contents of Piggy Bank
421473=A6-A5=C6/365*$B$2=D6*F5=F5+E6+B6
421543=A7-A6=C7/365*$B$2=D7*F6=F6+E7+B7
=A7+73=A8-A7=C8/365*$B$2=D8*F7=F7+E8+B8
421683=A9-A8=C9/365*$B$2=D9*F8=F8+E9+B9
421750=A10-A9=C10/365*$B$2=D10*F9=F9+E10+B10
Title: Re: Growing your kiddo's MM
Post by: Leggo on May 31, 2015, 08:34:25 PM
Thank you!  Can't wait to have a sit down with the kiddos once school lets out (next week!)