wheat  occupies 21.8 percent  of the total area under food grains
wheat productivuty of haryana =4680 kg per hectare
of india = 2703 kg/hectare
of world = 2717 kg/he
uk(highest) = 7879Kg/ha
followed by France(7321Kg/ha.)and Egypt(6206Kg/ha.).

http://dacnet.nic.in/dwd/faqs1.htm

How wheat productivity changed in India

http://dacnet.nic.in/dwd/wheat_prod1/history.htm

A page worth reading

Wheat productivity

the productivity of wheat in 2011 in haryana is 4650 kg per hectare whereas in 1950-1951, it was 663 kg per hectare.
4650/ 663= 7.01357

and 7^(1/60) = 1.03296
so, that means the wheat  productivity has grown up by 3.3 percent every year in last 60 years.