
                             ***** VATCalc *****
                                   _______

                         ***** VAT Calculator *****
              ***** Copyright (C) Alexander Buckley 1991 *****
                    ____________________________________

                              ***** !Help *****
                                    _____


Introduction ________________________________________________________________

VATCalc is a simple little program which works out various pieces of
VAT-related information for you. The results can be saved to disc or exported
to another program.


Operation ___________________________________________________________________

Double-clicking on the !VATCalc icon in a filer window loads VATCalc, and
it's icon will install on the icon bar. This icon provides a standard
two-item menu consisting of Info and Quit, both of which do as expected.

Clicking <SELECT> on the icon bar icon produces the main calculator window.
Here you can enter 1) the VAT rate, 2) the cost price (the cost of the item
excluding VAT), 3) the VAT paid (the amount of VAT payable on the item) and
4) the total (the sum of the cost price and VAT paid).

There should always be a value for the rate (if there is not, it will be
taken as 0%), and any value should be to one decimal place only (any more
will be rounded to one d.p.). (You only have to enter one of the three items
(cost price, VAT paid and total) and the program will work out the two values
not given. Any supplied value is taken as pounds if there are no decimal
places, otherwise it is taken as pounds and pence.

Clicking Cancel will return the rate of VAT to its original value that it had
at the start of the program. Clicking Clear will blank the three main fields,
whilst clicking Calculate (or pressing <RETURN> in the total field) will work
out the necessary values.

Clicking <MENU> in the calculator window produces a context-sensitive menu,
allowing you to save any of the four items in the window, or all of them.
Please note that the program only gets the contents of the four fields when
either Cancel (for the VAT rate) or Calculate (for the other three) is
clicked. You could, for example, type in a value into any of the three main
fields but not click Calculate (or press <RETURN> in the total field), in
which case the last four menu items would remain faded.

For whatever you (can) save, a standard "Save as:" dialogue box is provided
to drag the file icon to either a filer window or to another application. To
be honest, the ability to save to disc is only provided for completeness, as
I would imagine that VATCalc is most useful when the results are dragged into
another application.

When VATCalc starts up, it takes its original VAT rate from a file called
"VATRate" in the !VATCalc directory. By changing the number in this file, you
can alter the original VAT rate (the value which the rate item returns to
when you click on Cancel) as VAT itself changes. If there is no file, VAT is
takes to be the current amount at the time of writing, namely 17.5%. If the
file is empty, VAT is taken to be 0%.


Rounding up _________________________________________________________________

This is a very important point, as it can appear that the program can't add
up! The reason for this is that the program will ALWAYS round values up to
make a whole number of pence, eg, 15.001 becomes 15.01, 21.016 becomes
21.02, or 60.999 becomes 61 - you get the idea. Anyway, the program can
appear to do some funny things because of the order in which the values are
worked out.

What it does it to look first at the cost price, and if it has something in
it, work out other two. These answers will always "add up". If there is
nothing in it, the program will look at the VAT paid, and if occupied, work
the other two out - again, they will always "add up".

However, if you enter a total, although the other values will be correctly
worked out, when rounded-up, they will not add up (literally) to the total.
This is because of the need to round-up to whole pence. The only times they
will add correctly is for total's like 117.50 (assuming 17.5% VAT), which
works out to exactly 100 and 17.50 for the other two - perfect. I have
assumed that it is better always to round-up if possible, so that you
don't under-charge of under-pay. If anyone does not like this (and this is
perfectly possible), contact me and I'll change it - this program is supposed
to be useful as possible.


History _____________________________________________________________________

Any of you who have read Computer Shopper, August 1991, will probably have
seen a little Windows 3 PD program called "VAT Calculator" mentioned by Huw
Collingbourne in his Opinion column. He rates it quite highly on the grounds
that it's simple but extremely handy - and therefore "a jolly good thing".
Never being one to miss a good opportunity (most of the time), I decided to
do a version for the Archimedes.

I know nothing about the Windows 3 version apart from what it's window looks
like (exactly the same as VATCalc's one - I purposely designed it to be the
same) and how it behaves (though that's a bit obvious). I assume that the W3
version can transfer the values to other programs via the Windows Clipboard
or by DDE (Dynamic Data Exchange), so it's just as well that VATCalc can.


Acknowledgements ____________________________________________________________

Many thanks must go to the following people :

1) The author of the Windows 3 version of VAT Calculator, for writing it in
   the first place!
2) Huw Collingbourne, for reviewing the program and thus bringing it to my
   attention!
3) Daniel Bennis, for suggesting the "Read VAT from file" feature.
4) Richard Watson, for all his help and encouragement on everything.


If you want to contact me, I would be pleased to hear from you via :

Snail-Mail  :  19 Corringham Road,
               Wembley Park,
               Middlesex,
               HA9 9PX

Telephone   :  081-904 8878 (reasonable hours, please)


Alexander Buckley
14 August 1991
