881.70 yards per minute is about 0.00000005 times as fast as The Speed of Light.

The speed of light (and all other electromagnetic radiation) in a perfect vacuum is known as "c" and measures exactly 19,671,421,100 yards per minute, per the formal definition of the meter. While visible light travels close to this speed in air, it slows to 13,114,280,800 yards per minute when passing through the glass of a typical window.

In other words, it's 0.00000004482136770 times the speed of The Speed of Light, and the speed of The Speed of Light is 22,310,787.30 times that amount.

(C) (in a vacuum)The speed of light (and all other electromagnetic radiation) in a perfect vacuum is known as "c" and measures exactly 19,671,421,100 yards per minute, per the formal definition of the meter. While visible light travels close to this speed in air, it slows to 13,114,280,800 yards per minute when passing through the glass of a typical window.