# Table 1 Method used to calculate gender gaps in the Gender Equity Index (proposed by Social Watch) and the modified Gender Equity Index

Social watch gender equity index (SW) Modified gender equity index
SW defines the corresponding gap between women (W) and men (M) as: $\mathit{Gap}.c=\frac{%\mathit{Wc}}{%\mathit{Mc}}.\mathit{WF}{P}^{-1}$ where % Wc and % Mc are, respectively, the% of W and M with the characteristic The MGEI compares the proportions of women and men with a particular characteristic (c) in absolute terms (difference P Wc  − P Mc ), standardising the result so that the “modified gap” (MGap. c) is defined as:
(c), and $\mathit{WFP}=\frac{\mathit{Po}{p}_{W}}{\mathit{Po}{p}_{M}}$ is the weight of the female population. $\mathit{MGap}.c=\frac{{P}_{\mathit{Wc}}-{P}_{\mathit{Mc}}}{{P}_{\mathit{Wc}}+{P}_{\mathit{Mc}}}$
This expression of the gender gap is simplified by replacing the inverse value of the weight of the female population: $\begin{array}{l}\mathit{Gap}.c=\frac{%\mathit{Wc}}{%\mathit{Mc}}.\frac{\mathit{Po}{p}_{M}}{\mathit{Po}{p}_{W}}=\frac{\mathit{Wc}.100/\mathit{Pop}}{\mathit{Mc}.100/\mathit{Pop}}.\frac{\mathit{Po}{p}_{M}}{\mathit{Po}{p}_{W}}\\ =\frac{\mathit{Wc}}{\mathit{Mc}}.\frac{\mathit{Po}{p}_{M}}{\mathit{Po}{p}_{W}}=\frac{\mathit{Wc}}{\mathit{Po}{p}_{W}}.\frac{\mathit{Po}{p}_{M}}{\mathit{Wc}}\end{array}$
Where Pop is the total population.
The proportions have values of between 0 and 1, from which it results that: − (P Wc  + P Mc ) ≤ P Wc  − P Mc  ≤ P Wc  + P Mc , whilst dividing by P Wc  + P Mc results in − 1 ≤ MGap. c ≤ 1.
If ${P}_{\mathit{Mc}}=\frac{\mathit{Wc}}{\mathit{Po}{p}_{W}}$ and ${P}_{\mathit{Mc}}=\frac{\mathit{Mc}}{\mathit{Po}{p}_{M}}$ are respectively the proportions of W and M with a particular characteristic (c) out of their corresponding totals, the gap suggested by SW allows the following formulation: $\mathit{Gap}.c=\frac{{P}_{\mathit{Wc}}}{{P}_{\mathit{Mc}}}$
Once the gender gap has been calculated, the GEI is calculated as the arithmetic mean of the 3 gaps:$\mathit{GEI}=\frac{\mathit{Empowerment}.\mathit{Gap}+\mathit{Economic}.\mathit{Act}.\mathit{Gap}.+\mathit{Education}.\mathit{Gap}}{3}$
Social Watch GEI values:
0 (inequity) - 1 (gender equity)
Modified GEI values:
- 1 (Women inequity) 0 (equity) 1 (Men inequity) 