2001

2002

2003

2004

2005

Total Headcount

22,609

23,609

23,803

24,149

24,487

Under 18 years

3,810

3,614

3,482

4,062

4,335

18-19 years

4,258

4,041

3,877

3,899

3,796

20-21 years

3,890

3,790

3,702

3,545

3,181

22-24 years

5,598

5,885

5,917

5,694

5,627

25-29 years

2,992

3,622

3,997

4,122

4,559

30-34 years

879

1,065

1,208

1,244

1,355

35-39 years

465

568

572

606

641

Over 39 years

711

1,024

1,048

967

980

Unknown

6

0

0

10

13

Mean Age

22.4

23.1

23.3

23.1

23.2