Add institutional_trading.parquet and README.md

README.md

@@ -14,7 +14,7 @@ description: >-
 
 ```python
 from datasets import load_dataset
-df_institute = load_dataset("sovai/institutional_trading", split="train").to_pandas().set_index(["institution_id","date"])
+df_institute = load_dataset("sovai/institutional_trading", split="train").to_pandas().set_index(["ticker","date"])
 ```