Peso offers in Argentina are out of date in weeks. Is anyone indexing pay to the dollar?

We opened a 45-person engineering centre in Buenos Aires last year, part of a media technology company of about 1,300. Salaries are in pesos as required, reviewed quarterly, most recently by 18%.

Even so, our competitors for talent are foreign companies paying contractors in dollars, and we have lost seven engineers to them since January. Local management wants to set salaries as a dollar amount converted each month at a reference rate.

I am wary of promising a currency link in an employment contract. Is anyone doing this for regular employees, and which rate do you use?