1. Logic Function Review

2. Purpose of using logical functions
To establish pre-defined conditions with pre- defined results in a worksheet.
Examples:
IF sales > $1000, then commission = 10% of sales, else commission = 5% of sales.
IF current balance < $500, then credit approval is TRUE, else credit approval is FALSE.
IF current balance < $500 or credit rating is good, then credit approval is TRUE, else credit approval is FALSE.
IF credit rating type 1 is good and credit rating type 2 is good, then credit approval is TRUE, else credit approval is FALSE.

3. Current Past Due Balance
Sample sheet for class presentation
Accounts Receivable Department - Customer Credit Analysis
Customer Name
Current Credit Limit
First Purchase Date
Previous Year's Sales
Current Year's Sales
Current Past Due Balance
D&B Appraisal (1 Best)
D&B PAYDEX (100 Best)
D&B Risk Class
Athletic Gear Corp.
$ 9,000
5/15/2001
$ ,382
$ 11,952 $ 4 15 A3
Baltimore O's
30,000
12/19/1998
10,033
7,789 - 1 51 A2
Baseball & More
20,000
6/21/2008
60,009
55,342
5000 2 70 B1
Canadian Ski Club
9/13/2011
35,039
50,921
1,500 43
Concord Pro Shop
10/15/2011
1,925 91 A1
Everything Golf
25,000
10/6/2000
15,221
9,483
2,899 3 76
Lake Pro Shops
45,000
4/17/2005
80,498
81,126 87
Mars Dept. Store
27,000
1/16/2009
35,354
20,666 94
RG Bradley
7/8/2007
90,970
18,343
10,000 21
RX for Sports
15,000
8/14/2010
5,663
3,014
775 59 B2
School Sports Supply
6/3/1999
50,278
32,338
4,000
Ski World
3/4/2000
25,864
28,154 82

4. Overall structure of logical conditions
IF relational condition THEN do something ELSE do something else
These types of logical computer decisions are black and white right or wrong – there is no “gray” area.

5. Determining a company’s credit worthiness, true or false?
Example of boolean logical condition
Determining a company’s credit worthiness, true or false?
IF Dunn & Bradstreet appraisal <= 2
THEN
TRUE in evaluation column
ELSE
FALSE in evaluation column
Write the Excel statement:

6. Using Relational Operators

7. Boolean functions
To determine if the relational condition is TRUE or FALSE
Can be used to compare values, text labels, dates
Implemented in Excel by starting a formula and using a relational operator:
=B4 * .1 > B5
=B4 < B5

8. Compound Boolean Logical Functions
AND
Used to determine if all conditions are TRUE OR
Used to determine if any condition is TRUE

9. Determining a company’s credit worthiness, true or false?
Example of compound boolean logical condition
Determining a company’s credit worthiness, true or false?
IF D&B appraisal <= 2 AND past due balance <= 0
THEN
TRUE in evaluation column
ELSE
FALSE in evaluation column
Write the Excel statement:

10. Determining a company’s credit worthiness, true or false?
Example of compound boolean logical condition
Determining a company’s credit worthiness, true or false?
IF D&B appraisal <= 2 OR past due balance <= 0
THEN
TRUE in evaluation column
ELSE
FALSE in evaluation column
Write the Excel statement:

11. More ANDs and ORs Write the Excel statements:
Result is still always either “TRUE” or “FALSE”
Create 4 different rules:
D&B Appraisal of at least 2
No past due balance
D&B PAYDEX of at least 70
D&B risk class of A1
Final rule 1 checks to see if they are all true
Final rule 2 checks to see if any of the rules are true.
Write the Excel statements:

12. IF Function Review IF function
Boolean logical function that returns different values other than simply TRUE or FALSE depending on the specified condition.
Can be single, compound or nested.

13. Determining whether sales are going up or down
Example of single logical condition
Determining whether sales are going up or down
IF Current year’s sales > previous year’s sales
THEN
“sales going up” in evaluation column
ELSE
“sales going down” in evaluation column
Write the Excel statement:

14. Determining credit worthiness
Example of compound logical condition
Determining credit worthiness
IF D&B appraisal is 1 or 2, and D&B PAYDEX is higher than 70 and D&B risk class is A1
THEN
“good risk” in evaluation column
ELSE
“bad risk” in evaluation column
Write the Excel statement:

15. Think about more complex conditions…
D&B Appraisal
D&B PAYDEX
D&B Risk Class
Credit worthiness? 1
Anything
Good risk 2
> 80
< = 80 A1
not A1
Bad risk
>2

16. Determining credit worthiness revisited
Example of nested logical condition
Determining credit worthiness revisited
IF D&B appraisal is 1
THEN
“good risk” in evaluation column
ELSE
IF D&B appraisal is 2
IF D&B PAYDEX > 80
IF D&B risk class = 1
“bad risk” in evaluation column

17. Nested IF statements are complex
The IF statement for the nested IF looks like this:
=IF(G4=1,"good risk",IF(G4=2,IF(H4>80,"good risk",IF(I4=A1,"good risk","bad risk")),"bad risk"))
Let’s split it into pieces:
=IF(G4=1,"good risk",IF(G4=2,IF(H4>80,"good risk",IF(I4=A1,"good risk","bad risk")),"bad risk"))

18. Practice nested IF on something new!
Let’s say that we want to calculate a “graduated” finance charge based on the following table:
Field
Condition
Finance Charge
Past due balance
> $5000
12% of total past due
> 3000 and <= 5000
10% of total past due
> 1000 and <= 3000
8% of total past due
<= 1000
2% of total past due

19. Translate specifications into IF/THEN/ELSE
IF past due balance > 5000
THEN finance charge = .12 * past due balance
ELSE
IF past due balance > 3000
THEN finance charge = .10 * past due balance
IF past due balance > 1000
THEN finance charge = .08 * past due balance
THEN finance charge = .02 * past due balance

20. Make conditions easier with LOOKUP
Allows you to use tables of data to “look up” values and insert them in another worksheet location, or other worksheet.
Lookup tables store data and organize it into categories for comparison.
Can be constructed for either an exact match or a range match.

21. Using VLOOKUP for an exact match
Searches a lookup table and based on the value used for comparison, retrieves a matching value from the lookup table.
Let’s use the D&B Risk Class for a vertical lookup table. If the D&B Risk Class is A1, A2 or B1, then it is a good risk.
Syntax of exact match VLOOKUP:
VLOOKUP(comparison value to lookup, table, column of result, FALSE)

22. Using VLOOKUP for a range match
Searches a lookup table and based on the value used for comparison, retrieves a value from the lookup table using >= logic
Let’s use the finance charge example from slide #19
Syntax of range match VLOOKUP:
VLOOKUP(comparison value to lookup, table, column of result, TRUE)