Pareto analysis is used to judge frequency and importance of various items, e.g. faults, errors etc. The Pareto chart is based on ordering various items by their amount. The Pareto 80/20 rule says that 80% of problems is caused by 20% of causes. The rule has been found approximately valid in many practical situations. When expenditures or financial losses are known, the Pareto analysis can be performed on them as well.

Pareto Analysis - Pdf manual

Task: Classification of mechanical fault causes

Defect Cause	Count	Repair Cost
Flange Packing	40	5
Corrosion A	3	60
Corrosion B	35	20
Turn-cock	14	130
Cover B	5	52
Nuts	62	13
Condenser	21	28
Ball bearing H	5	300
Ball bearing M	17	220
Hose	36	40

Pareto Chart
Task name :	Pareto1
Cost unit :	USD
Occurrences
Causes	Count	Cost	Occurrence ratio	Cumulative ratio	Cost per occur.	Cost ratio
Nuts	62	13	26,05	26,05	806	7,17
Flange Packing	40	5	16,81	42,86	200	1,78
Hose	36	40	15,13	57,98	1440	12,82
Corrosion B	35	20	14,71	72,69	700	6,23
Condenser	21	28	8,82	81,51	588	5,23
Ball bearing M	17	220	7,14	88,66	3740	33,29
Turn-cock	14	130	5,88	94,54	1820	16,2
Ball bearing H	5	300	2,1	96,64	1500	13,35
Cover B	5	52	2,1	98,74	260	2,31
Corrosion A	3	60	1,26	100	180	1,6
Total :	238				11234
Cost
Causes	Count	Cost	Occurrence ratio	Cost per occur.	Cost ratio	Cumul. cost ratio
Ball bearing M	17	220	7,14	3740	33,29	33,29
Turn-cock	14	130	5,88	1820	16,2	49,49
Ball bearing H	5	300	2,1	1500	13,35	62,84
Hose	36	40	15,13	1440	12,82	75,66
Nuts	62	13	26,05	806	7,17	82,84
Corrosion B	35	20	14,71	700	6,23	89,07
Condenser	21	28	8,82	588	5,23	94,3
Cover B	5	52	2,1	260	2,31	96,62
Flange Packing	40	5	16,81	200	1,78	98,4
Corrosion A	3	60	1,26	180	1,6	100
Total :	238			11234