Bert and Ernie, residents of a separate property state, have been in a committed relationship since 1969. They purchased their NYC brownstone for $100,000 in 1976 as Joint Tenants with a Right of Survivorship. Bert contributed $25,000 and Ernie contributed $75,000 towards that cost. In 2021, Bert passes away when the property has a fair market value of $16,000,000. What value is includable in Bert's estate?