What evidence does this author provide to show that colonies were a negative financial drain on the Europeans?

Full Question:

The struggle for colonies does not result only in cash losses. There were also lives lost, wars fought, and hatreds aroused which threatened new wars. . . .Italy’s trade with her colonies in 1894-1932 was worth 5,561 million lire [about $1,100 million]. This was less than one percent of her total foreign trade in the same period. In fact, her expenditures on colonies for that time was 6,856 million lire. Obviously colonies cost more than they are worth in trade.

What evidence does this author provide to show that colonies were a negative financial drain on the Europeans?

This one is quite straightforward.

A quick look at the figures and a simple calculation will show that the colonies were a negative financial drain on the Europeans

Explanation:

Value of trade with colonies between 1894-1932 = 5,561 Million Lire

Total expenditure on the colonies t that time = 6,856 Million Lire

Profit (or Loss) = Revenue (or Trade) Less Expenditure:

That is: (5,561-6,856) Million

Loss = -1,295 Million Lire

As evidenced in the calculation, The author shows that imperialism was not profitable for the colonial authorities. A lot of money and lives were lost by the  European countries in wars with the colonies.  Italy for instance is an example of a recipient of this harsh economic colonial realities.

Cheers!