Please answer a question about the following article about Cotton:

Though known since antiquity the commercial growing of cotton in Egypt only started in 1820's, following a Frenchman, by the name of M. Jumel, propositioning the then ruler, Mohamed Ali Pasha, that he could earn a substantial income by growing an extra-long staple Maho (Barbadence) cotton, in Lower Egypt, for the French market. Mohamed Ali Pasha accepted the proposition and granted himself the monopoly on the sale and export of cotton in Egypt; and later dictated cotton should be grown in preference to other crops. By the time of the American Civil war annual exports had reached $16 million (120,000 bales), which rose to $56 million by 1864, primarily due to the loss of the Confederate supply on the world market. Exports continued to grow even after the reintroduction of US cotton, produced now by a paid workforce, and Egyptian exports reached 1.2 million bales a year by 1903.

How high had cotton revenues risen by the time of the American Civil War?
$56 million