Four-yearly Wage Structure Survey 
Sampling errors
Main NCO-11 groups. National total
Units: %

All occupations	0.37	
A. Directors and managers	3.89	
B. Health and education-related scientific and intellectual technicians and professionals	1.82	
C. Other scientific and intellectual technicians and professionals	1.47	
D. Technicians, support professionals	1.07	
E. Office employees that do not provide customer service	1.37	
F. Office employees that provide customer service	1.96	
G. Workers in catering and trade services	1.49	
H. Workers in health and personal care services	1.62	
I. Workers in protection and security services	4.31	
J. Skilled agricultural, livestock, forestry and fishing sector workers	7.85	
K. Skilled construction workers, except machinery operators	1.83	
L. Skilled workers in the manufacturing industries, except installation and machinery operators	1.28	
M. Installation and fixed machinery operators and assemblers	1.55	
N. Mobile machinery drivers and operators	1.87	
O. Unskilled workers in services (except transport)	1.42	
P. Agricultural, fishing, construction, manufacturing and transport industry labourers	1.88	
Notes:
Source: National Statistics Institute