Post Danmark regularly examines how long

that goes before the letters are delivered.

Post Danmark's goal for good quality

Ordinary letters: At least 95% delivered the next day

Finance letters: At least 95% delivered no later than 3 days after

Ordinary letters

delivered the next day

96.1%

94.7%

95.1%

93.1%

92.3%

93.0%

93.9%

94.1%

92.1%

94.3%

95.3%

94.8%

92.2%

93.5%

93.1%

95.5%

93.3%

95.2%

96.2%

95.2%

94.3%

95.0%

94.9%

95.7%

94.7%

92.4%

94.4%

94.9%

92.9%

93.7%

96.0%

95.7%

94.6%

94.9%

95.4%

94.8%

94.9%

94.4%

96.0%

95.3%

95.6%

95.4%

95.3%

93.5%

94.1%

94.4%

93.9%

94.1%

94.5%

94.9%

95.2%

93.6%

93.1%

92.0%

95.1%

92.8%

95.0%

Box plot:

90 91 92 93 94 95 96 97 98 99

Ordinary letters

Finance letters

The table to the right shows what percentage of the regular letters were delivered on time in 57 surveys

made from 1995 to 2009.

Questions

Task 4: Letter quality

4.1 What percentage of the ordinary letters were in

average delivered the next day? Use spreadsheets.

4.2 Fill in the table for financial letters. Use spreadsheets.

4.3 In what percentage of the surveys for the two

types of letters, Post Danmark lived up to the goals of

good quality? Use spreadsheets.

4.4 Describe Post Danmark's letter quality based on the two

box plot.