TKENDS IN EARNINGS 39 major industrial groups are also collected under the Collection of Statistics (COS) Act 1953 as part of the Annual Survey of Industries (ASI) and published by the Labour Bureau.6 They refer to the larger units or the Census sector. These data, though collected separately for i) workers and ii) supervisory/managerial staff, are published as an average for all employees. They cover, therefore, not only all workers irrespective of pay range but also non-workers. Venkataramaiah7 has built an index of per capita real earnings of factory employees based on ASI data but not strictly comparable with the COS data on earnings.8 The Major Limitation A major limitation with these data on earnings, hardly touched upon by the users of these data, is that they arc beset with conceptual problems which impair comparability and reliability. This arises from four main sources: i) definition of earnings» ii) coverage of employees, iii) changing skill composition of workers whose earnings are being studied and iv) choice of a price deflator for estimating real per capita earnings. The definition of ^earnings" varies widely from one source to another, mainly because of difference in the treatment of allowances and other benefits (both in money and in kind). Some times earnings may refer only to basic wages/salaries; in most cases, however, some or all other allowances, including annual bonus and retirement benefits, arc included. The POW Act collects data on wages which relate to a) basic wages, b) cash allowances such as dearness, compensatory, house rent, production/efficiency bonus. It excludes the value of certain benefits in kind such as house accommodation, supply of light, water and so on. Travelling allowance or value of any travel concession is also excluded. On the other hand, the COS Act defines earnings as all those items included under the POW Act but excluding annual or profit sharing bonus. However, imputed value of certain individual benefits in kind such as transport, accommodation, light, water and others are included. Both refer to gross earning, that is, before deductions for fines, damages, taxes, contribution to provident fund and Employees State Insurance. It may be seen that besides the above differences between these two sets of data there are certain other items of labour cost which both do not cover. For example, employer's contribution to the provident fund, gratuity payable on discharge and imputed value of certain group benefits in kind such as schools, creches, hospitals, canteens are not included. Table I