FORM 10-K

49

MDU RESOURCES G ROUP, INC.

2007

2006

2005

2004

2003

2002

Electric

Retail sales (thousand kWh)

2,601,649

2,483,248

2,413,704

2,303,460

2,359,888

2,275,024

Sales for resale (thousand kWh)

165,639

483,944

615,220

821,516

841,637

784,530

Electric system summer generating and firm

purchase capability -- kW (Interconnected system)

571,160

547,485

546,085

544,220

542,680

500,570

Demand peak -- kW (Interconnected system)

525,643

485,456

470,470

470,470

470,470

458,800

Electricity produced (thousand kWh)

2,253,851

2,218,059

2,327,228

2,552,873

2,384,884

2,316,980

Electricity purchased (thousand kWh)

576,613

833,647

892,113

794,829

929,439

857,720

Average cost of fuel and purchased power per kWh

$ .025

$ .022

$ .020

$ .019

$ .019

$ .018

Natural Gas Distribution*

Sales (Mdk)

52,977

34,553

36,231

36,607

38,572

39,558

Transportation (Mdk)

54,698

14,058

14,565

13,856

13,903

13,721

Weighted average degree days ­

% of previous year's actual

Montana-Dakota

107%

95%

100%

94%

96%

109%

Cascade

101%

­

­

­

­

­

Pipeline and Energy Services

Transportation (Mdk)

140,762

130,889

104,909

114,206

90,239

99,890

Gathering (Mdk)

92,414

87,135

82,111

80,527

75,861

72,692

Natural Gas and Oil Production

Production:

Natural gas (MMcf)

62,798

62,062

59,378

59,750

54,727

48,239

Oil (MBbls)

2,365

2,041

1,707

1,747

1,856

1,968

Average realized prices (including hedges):

Natural gas (per Mcf)

$ 5.96

$ 6.03

$ 6.11

$ 4.69

$ 3.90

$ 2.72

Oil (per barrel)

$59.26

$50.64

$42.59

$34.16

$27.25

$22.80

Proved reserves:

Natural gas (MMcf)

523,737

538,100

489,100

453,200

411,700

372,500

Oil (MBbls)

30,612

27,100

21,200

17,100

18,900

17,500

Construction Materials and Contracting

Sales (000's):

Aggregates (tons)

36,912

45,600

47,204

43,444

38,438

35,078

Asphalt (tons)

7,062

8,273

9,142

8,643

7,275

7,272

Ready-mixed concrete (cubic yards)

4,085

4,588

4,448

4,292

3,484

2,902

Recoverable aggregate reserves (tons)

1,215,253

1,248,099

1,273,696

1,257,498

1,181,413

1,110,020

* Cascade was acquired on July 2, 2007. For further information, see Item 8 -- Note 2.