The word gerbil is a diminutive form of  jerboa , though the jerboas are an unrelated group of rodents occupying a similar ecological niche.
A variance is a form of equitable relief that allows a property owner to bypass local zoning laws so they can use their land in the most efficient manner possible. When unusual circumstances make it difficult for a property owner to comply with local zoning laws, cities and counties may grant what are known as variances to allow property owners to circumvent the traditional zoning laws in an area.
The most widely used real estate benchmark, the NCREIF Property Index (NPI), is composed of approximately 6,950 institutional grade, operating properties valued at over $443 billion. The NPI is designed to measure the performance and return characteristics of a set of core properties on an unleveraged basis.