Sayyiduna Abu Musa (may Allah be pleased with him) said: "Whoever fasts the whole year, Hell will be made narrow for him like this." And he made the hand sign for ninety.
Shu'bah did not narrate it as marfu' (as a saying of the Prophet (peace and blessings be upon him)).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8478