2010-08-26 先月の最終木曜日 Access IIf(Weekday(DateSerial(Year(Date()),Month(Date()),0))>=5,DateSerial(Year(Date()),Month(Date()),0)-Weekday(DateSerial(Year(Date()),Month(Date()),0))+5,DateSerial(Year(Date()),Month(Date()),0)-Weekday(DateSerial(Year(Date()),Month(Date()),0))-2)