Even if the average percentage of male blood donors is known, it is difficult to calculate its influence on the prevalence of MC.
It is difficult to calculate the exact number of young homeless people in the UK.
"While it is difficult to calculate precisely what value these channels bring, it is likely to be considerable".
It is difficult to calculate whether one state got more out of the deal than the other.
Even 10 years after the invasion, it is difficult to calculate the extent of the war's toll.
In this situation, when the total number of those infected is unknown, it is difficult to calculate a disease's death rate.
Another drag on earnings, though it is difficult to calculate, is the impact on the Ford Motor Company from the tire recall by Firestone.
For those who have yet to hear how much their insurance will cover, it is difficult to calculate casualty losses, he noted.
It is difficult to calculate the reach of our local programme but we estimate this year's projects supported nearly 700 members of our local community.
While it is difficult to calculate exactly how many people use R, those most familiar with the software estimate that close to 250,000 people work with it regularly.
The outcome is that it is difficult to calculate the properties of hadrons, in particular their masses, which depend on the energy tied up in the interactions between the quarks they contain.
