To compute an interquartile range using this definition, first remove observations from the lower quartile. Then, remove observations from the upper quartile. Then, from the remaining observations, compute the difference between the largest and smallest values.
Know the meaning of the carrying value. The carrying value is a calculation performed by the bond issuer, or the company that sold the bond, in order to accurately record the value of the bond discount or premium on financial statements. The discount or premium is amortized, or spread out, over the term of the bond.
Trailing twelve months is a unit of measurement used to indicate an organization's financial standing in the market. I think this is what is being referred to in the quote. From Wikipedia : Trailing Twelve Months (TTM) is a measurement of a company's financial health used in finance. It is measured by using the income statements from a company's reports (such as interim, quarterly or annual reports), to calculate the income for the twelve-month period immediately prior to the date of the report.