Hi Group

I have a table with data stored like below:

Date MCName PBNo
01/01/2009 CM1 1
01/01/2009 RS2 1
01/01/2009 RH1 5
02/01/2009 CM1 2
02/01/2009 RH1 6
03/01/2009 RS2 2
03/01/2009 CM1 3
05/01/2009 CM1 4
05/01/2009 RH1 7

I have a continous form which displays the data for each day i.e.

01/01/2009
CM1 1
RS2 1
RH1 5

What I would like to do is add a column to my form that would show the
previous PBNo for each MCName on the form.

05/01/2009
CM1 4 3
RH1 7 6

The purpose of the second (previous) PBNo is to determine if there are
any gaps (non sequential numbering) which would be highlighted on the
form using a simple conditional format.

My problem is how to acheive this as MCName(s) are scheduled so not
checked everday they could be as far as a fortnight between checks.
Therefore I would have to look for the previous date that a particular
MCName was checked and then extract the PBNo from that record. I was
thinking of somehow utilising the Dlookup function but I am unsure how
to go about it. Has anyone any ideas/clues how I should proceed.

Any help would be appreciated.

I am using Access 2002 SP3 on XP Pro SP2