Pakistan has left India far behind in terms of improving water and sanitation access for their citizens, reveals a new performance index released on Friday.

While Pakistan was ranked five in the new index developed by The Water Institute at the University of North Carolina at Chapel Hill`s Gillings School of Global Public Health in the US, India occupied an unenviable 92nd position.

High-performing countries for 2015 are those that achieved significant improvement in recent years compared to their peers. Low-performing countries are those that showed stagnation or decline in recent years compared to their peers.

India`s ranking as a bottom-performer predates the recent launch of the "Clean India Mission" by Prime Minister Narendra Modi.

Sub-Saharan Africa countries including Mali, South Africa, and Ethiopia are also among the top performers world-wide in spite of modest resources, according to the WaSH Performance Index that evaluates country performance in improving access to water and sanitation and in eroding inequalities in access.

Other high performers include China, El Salvador, Niger, Egypt, and Maldives. Conversely, Russia, the Philippines and Brazil were bottom performers .

The index compares countries of all sizes and income levels. Using this method, the report revealed that a country`s gross domestic product did not determine performance in improving water and sanitation for its citizens.

"This means that even countries with limited resources can make great strides if they have the right programs in place," said co-author of the report Jamie Bartram, director of The Water Institute at UNC.

"National governments, NGOs, and aid agencies can direct their resources toward building systems and capacity for action in countries that are lagging, and toward implementation where those capacities are in place and performing," Bartram noted.