1. Introduction
The Relative Development Index (RDI) is a composite index that measures the relative achievement of subregions of the country in dimensions of development. Variables included in the construction of the index are limited to those derived from housing and population censuses, these being the only sources of comprehensive data at subregional level.
A set of RDIs for administrative regions, namely Municipal Wards and Village Council Areas, and for the Island of Rodrigues was first constructed and published in 1996. The indices were computed based on data collected at the 1990 Census and according to the methodology of the Human Development Index (HDI) of the United Nations Development Programme (UNDP).
A new set of indices for these areas has been worked out using the 2000 Census data and the results are presented in this paper. For comparison purposes, all variables that were used in the construction of the previous indices have been included while the computational methodology has been modified slightly. The methodology is described in Section 2 and the results are given in Section 5.
2. Methodology
(a) Variables used
Variables used in the computation of the index are:
(i)

% of households having piped water,

(ii)

% of households having electricity,

(iii)

% of households having flush toilet,

(iv)

% of households living in dwellings made of concrete,

(v)

% of households having one or more rooms used for living purposes per person,

(vi)

% of households who own their dwelling,

(vii)

% of population aged 18 years and over having at least School Certificate or equivalent educational attainment,

(viii)

primary enrolment ratio,

(ix)

secondary enrolment ratio,

(x)

literacy rate of the population aged 12 years and over,

(xi)

employment rate of the population aged 12 years and over,

(xii)

% of the employed population in occupational groups 1,2 and 3 of the International Standard Classification of Occupations (ISCO), i.e. legislators, senior officials and managers; professionals; and technicians and associate professionals.

The values of the variables for each of the 145 areas (20 Municipal Wards, 124 Village Council Areas and Island of Rodrigues) listed in alphabetical order are shown in Table 1 (pages 712). Definitions of variables used are given at Appendix I (page 29). A map of the Island of Mauritius showing the location of wards and villages in coded forms is at Appendix II (page 30) while a description of these codes is given at Appendix III (pages 3133).
(b) Calculation of the index
A development index (H_{ij}) for each area is first calculated based on the methodology used for the HDI. If X_{ij} is the value of the development variable i for the area j, then the development index H_{ij} for area j based on variable i is defined as
H_{ij} = (X_{ij} – Min X_{ij})/(Max X_{ij} – Min X_{ij})
where Min X_{ij} is the minimum and Max X_{ij} is the maximum value of X_{ij} over all j areas for the years 1990 and 2000.
For example: Let us consider the development variable X_{11}: % of households with piped water for Albion VCA.
(i) X_{11} = 96.9388.
(ii) Min X_{1j} for the years 1990 and 2000 = 60.9444
(iii) Max X_{1j} for the years 1990 and 2000 = 100.00
(iv) Development index H_{11} = (96.9388 – 60.9444) / (100.00 – 60.9444 )= 0.9216
The minimum and maximum values used in the calculation of the previous set of indices published in 1996 were specific to 1990; indices thus derived gave the relative position of areas, or ranking, between the best and worst performers of that particular year. Over time, the achieved values of the development variables change across regions and so will the maximum and minimum values, so that a region may register a drop in its development indices (H_{ij}) in spite of improvement in components of development (X_{ij}) over time. To enable comparison over time, the methodology has been slightly modified in this paper: the minimum and maximum values are defined over the period of comparison, and not at each point in time separately. Thus, since we are comparing performance between 1990 and 2000, the minimum (or maximum) value for a given development variable is the minimum (or maximum) of all values of the variable, for all areas and for the years 1990 and 2000.
The index H_{ij} can take a value between 0 and 1, where index values near 0 indicate the least developed areas and index values near 1 indicate the most developed areas with respect to variable i. The Relative Development Index (RDI) for each area is obtained as a simple average of the values of the development indices (H_{ij}) over all variables.
The National Development Index is finally computed as the average of the relative development indices over all areas weighted by population size.
3. Limitations of the Relative Development Index
(a) Variables included in this exercise had to be limited to those available from censuses, given that the census is the only source of disaggregated data at small area level. Some important aspects of development such as health, longevity and access to various services are unfortunately not covered.
(b) Furthermore, some of the variables included, particularly those relating to living conditions and education, are intercorrelated and may be superfluous. Also, equal weighting or importance has been given to selected variables in the calculation of the RDI. The methodology used may therefore not best summarise the available information. However, actual values of the variables as well as the corresponding index values given in Table 1 (pages 712) and Table 2 (pages 1318) allow the use of other combinations and weightings.