The ratio of red to green is 9:4.

The pattern has rotational symmetry of order 2.

The yellow square in the bottom row is to the left of the green square in that row.

The ratio of green to yellow is 1:2.

The first two squares of the fourth row are the same as the first two squares of the fifth row.

There are three times as many reds as greens in the top row.

The ratio of blue to green is 1:1.

There are no blues in the bottom row.

The central column is red.

The ratio of yellow to red in the centre row is 4:1.

The two squares at the right of the 4th row are blue.

All of the red squares in the top row are to the left of the green square in that row.