How many years were listed under index when there were 157 countries sampled?
CREATE TABLE table_19948664_2 (index__year_ VARCHAR, countries_sampled VARCHAR)
SELECT COUNT(index__year_) FROM table_19948664_2 WHERE countries_sampled = 157
<s>[INST] Write mssql query to answer the following question given the database schema. Schema: CREATE TABLE table_19948664_2 (index__year_ VARCHAR, countries_sampled VARCHAR) Question: How many years were listed under index when there were 157 countries sampled? [/INST] SELECT COUNT(index__year_) FROM table_19948664_2 WHERE countries_sampled = 157 </s>