Negative Time-values

[Saturn]

I have the following question (or need):

I have a fixed table with cities and their respective GMT-values.
And of course many of the cities have negative GMT-values.


I will enter the Local Time for a specific city and want excel to (based on that table) to calculate GMT-time (when entering LT).

How can this be done?
I understand there could be some problems with negative values in TIME-formulas.

[oldchippy]

Take a look at this link, it may help you

http://www.cpearson.com/excel/datearith.htm#AddingTimes

[Saturn]

Thank you oldchippy

I have looked at this page and it might be useful
But it seems that the conclution is that excel doesnt accept negative time-values in a tabel (to be used for calculations).

Best regards Saturn

[oldchippy]

How about this one?

http://www.exceltip.com/st/Creating_...erter/949.html

[oldchippy]

This one could be useful too

http://wwp.greenwichmeantime.com/info/gmt.xls

[Saturn]

Thanks again oldshippy
For those of you who have the same need I have solved the problem by creating a table where I convert the GMT-values (both positive and negative values) into a 2400 'positive' hours tabel. The table could be, or should be, invisible.
Then GMT -11:00 becomes 01:00
Then GMT -04:00 becomes 08:00
Then GMT 00:00 becomes 12:00
Then GMT 06:00 becomes 18:00
etc. etc.
Saturn

[oldchippy]

Well done - and thanks for the feedback