Hello!

I have two questions:

I have such data:

A B
1 Date Weight (kg)
2 2008-02-27 103,5
3 2008-02-28 103,2
4 2008-02-29 103,0
5 2008-03-01 102,7
6 2008-03-02 not filled yet
7 2008-03-03 not filled yet
8 2008-03-04 not filled yet
etc. etc.

1)
How to get value of the last record entered. I mean:
how to get value of the first day entered in February 2008 and last value
of the last day of February 2008. So it the minus would like this:
A B
1 Date (month) Difference (kg) = Lost kg
2 Feb 2008 0,5 (because it equals 103,5-103,0)
3 March 2008 0 (because it equals 102,7-102,7)
4 etc. etc.

So above data would show me how much weight I lost in each/every month,
beginning
from Feb 2008 and finishing on the last month of the date entered in the
spreadsheet.
2)
How to get value of the first and last record entered overall. I mean:
how to get value of the first day entered in the whole data and last value
of the last day entered in the whole data. So it would be like this:
A B C
1 Date From Date To Difference (kg) = Lost kg
2 2008-02-27 2008-03-01 0,8 kg (because it equals 103,5-102,7)

So above data would show me how much weight I lost since the beginning of
loosing weight, that is
from Feb 2008 and finishing on the last month of the date entered in the
spreadsheet.

Thank you in advance for help
I really apprieciate it
Marcin from Poland