1 ship is 1 ship

Drawing pictograms is difficult. The Financial Times divides humans into four and amputates arms. Horrible. A little man represents 500 people. A loose arm 150. Strange currency.

Oversight overhauled - SEC employees and budget. - Source: Financial Times, 2010-08-27, page 5.
Source: Financial Times, 2010–08–27, page 5.

Here it works. The pictograms are ships which were attacked by pirates. Green: The pirates wanted to hijack the ship. Blue: They did hijack the ship. Each pictogram is one ship. Exactly one. And every time it’s about one ship. Just one. Not many or parts. Ship is ship.

Troubled waters: Attacks on ships in the first half of 2010, by region. - Source: Wall Street Journal, 2010-08-17, page 3.
Source: Wall Street Journal, 2010–08–17, page 3. I took it from him.

A pictogram works like: Count, what you want to show. Draw, what you want to count. Draw one of it. One per thing. If it doesn’t fit, no pictogram.