st: Looping through observations

[Laurie Molina <molinalaurie@gmail.com>]

Hello all,
Hope you are going well.

I am trying to do some calculations with a data set, but i am not very
familiar to stata programming.
The data set is about the time required achive a desired amount of saving.
For each observation in the data set, i have income, and saving rate.
But future income depends on the saving rate.

If i had only one observation i would do the following:

**** (I will omit the quotation marks of local variables).
local savings=0
local counter=0
while savings<10000 {
local counter=counter+1
local savings= income*savingsrate
income= income+ savings*(1+interestRate)
}

di counter
*****
But now, what i want to do is to create a variable, that contains, for
each observation the required time to achieve the desired amont of
savings.

In adition, i will use a huge data base (about 7,000,000 observations)
so i would like to need to create the minumum number of additional
variables.


I will appreciate any suggestions.

Thank you very much in advance!!

LM
*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/