By the time the last surviving ships reached Spain in October, half the original Armada was lost and some 15,000 men had perished — a higher toll than the 13,500 figure.

Evidence

Spanish Armada defeated | August 8, 1588 (History.com)

corroborated: 2 independent passages support this claim
XREF: connects to: Drake’s destruction of seasoned timber caused the Armada’s provisions to rot prematurely — John Sugden, Sir Francis Drake, 876; More than 13,500 Armada sailors and soldiers did not come home, the vast majority victims not of English cannon fire but of lack of food and water, virulent disease and incompetent organisation. — How the Spanish Armada Was Really Defeated; Over half the Spanish Armada ships were lost along with fifteen thousand men — John Sugden, Sir Francis Drake, 1080 (+1 more)

Only 60 ships are known to have reached Spain, many of them too badly damaged to be repaired, and perhaps 15,000 men perished. (similarity 0.94)
Over half the Spanish Armada ships were lost along with fifteen thousand men (similarity 0.90)
More than 13,500 Armada sailors and soldiers did not come home, the vast majority victims not of English cannon fire but of lack of food and water, virulent disease and incompetent organisation. (similarity 0.87)
No Spanish ship was lost other than the eight fire ships; the fireships’ main effect was forcing the Spanish to scatter. (similarity 0.80)
The Spanish lost 44 ships and estimates suggest that between 10,000 to 20,000 people were killed or went missing. (similarity 0.80)
Ships lost their anchors, and drifted out to sea to avoid catching fire, causing the Spanish ships’ formation to be completely broken. (similarity 0.79)