Useful formulas for use in MS Excel

Useful formulas for use in MS Excel

1. 2. 3. 4.

Dividing two numbers to get the product in pounds, shillings and pence Separating two strings bounded by a comma Using conditional statements Counting within a list delimited by sequential numbers

1. Dividing two numbers to get the product in pounds, shillings and pence A

B

C

D

1

Persons

Houses

RV

2 St. Marylebone

161860

16357

1053748

3 St. Pancras

198788

21852

925872

4 St. George's, Hanover Square

87771

10437

1076722

5 Islington

155341

20704

777632

E

F

G

To get the rateable value (RV) per person in pounds and shillings and pence, use the following three formulae in cells E2, F2, and G2: E2: =SUM(INT(D2/B2)) F2: =INT(SUM((D2/B2)-E2)*240/12) G2: =INT(SUM(((D2/B2)-E2-(F2/240*12)))*240) The formula for cell E2 gives the product of the division between the rateable value rounded down (using the function INT) to the nearest whole number. The formula in cell F2 takes the remainder of the previous sum, converts it to pennies, by multiplying by 240 and then divides by 12 to get shillings. Again an integer is given, rounding the whole number down. The formula in G2 repeats the calculations in F2 leaving a fraction of a pound which when multiplied by 240 gives the number of pence.

2. Separating two strings bounded by a comma A

B

C

NAME 1 Davies, Peter 2 Davis, Hezekiah

To separate the two elements of this variable use the following formulae in cells B1 and C1: B1: =LEFT(A1, FIND(",",A1)-1) C1: =RIGHT(A1,(LEN(A1)-FIND(",",A1)-1)) The LEFT and RIGHT functions are used to truncate a string, starting either from the left of that string or the right. The form is LEFT(string, number) where string is the cell you are interested in and number is the number of characters you want to take from that string. Thus =LEFT(shillings, 1) returns “s”. The second function used here is FIND. This function “finds” the character given in its first argument in the string given in its second argument. Thus =FIND(s, pounds) will return the number 6. Note that the FIND function only returns the character position of the first occurrence of that character. The first of these formulae then first finds the position of the comma in the string. (In the first case this is position 7. Then it truncates, from the left, a total of 6 characters (7 minus 1). This is necessary here because we don’t want the comma to appear in our result. The second of these formulae first finds the total length of the string, using the LEN function. Then finds the position of the comma. The latter number is subtracted from the first finding the length of the string after the comma. Because there is a space after the comma in both examples we remove one fewer character. The resulting number is used as part of the RIGHT function which takes the number of characters in its second argument from the right hand side of the first argument.

3. Using conditional statements Excel allows one to perform rudimentary conditional statements. Consider the census enumerators’ books where originally data relating to sex was denoted by being placed in the age columns: A

B

1

Frederick

2

Florence

3

Violet

4 5

Skipper

C

D

E

F

AGE_M

AGE_F

Head Wife

43

Skipper

Daughter

12

Ethel

Skipper

Daughter

11

Michael

Skipper

Son

4

Here we know that Frederick Skipper is male because his age is recorded in the Male column. Suppose that we wanted to add a column which gave the sex of each of these people, we would use the IF function. In cell G1 we would use the following formula: =IF(E1>0,"M","F"). This is saying that if the contents of the cell E1 (which is the male age) is greater than 0 then this person is a male and return the string “M”, otherwise (i.e., if the contents of E1 is less than 0 or missing) then return the string “F”. This is not entirely foolproof, because if the contents of the column for AGE_M contains anything at all, like a dash, it will return “M”. The basic syntax of the IF statement can be summarised as =if(condition is fulfilled, something, otherwise something else). IF statements are particularly useful because they can be nested. Nesting a condition, allows one to ask many (up to seven) conditions within a single statement. In the following example let us suppose that we want to classify the seven districts in Cornwall according to their population density. In our classification we want to have three groups, those districts which have a population density of less than one person per acre; those which have a population density of between one and five persons per acre and third, those which have a density of over five persons per acre. A

B

C

D

Acres

Population Density

1

Bomin MB

3312

5514

1.66

2

Bude-Stratton

4294

4459

1.04

3

Camborne-Redruth

22062

34920

1.58

4

Falmouth

1880

15040

8.00

5

Fowey MB

2979

2255

0.76

6

Helston MB

4014

4939

1.23

7

Launceston MB

2182

4273

1.96

=IF(D4