| symbol | Symbol representing the entity requested in the data. Here, it is the underlying symbol for the option. |
| contract_symbol | Contract symbol for the option. |
| eod_date | Date for which the options chains are returned. |
| expiration | Expiration date of the contract. |
| strike | Strike price of the contract. |
| option_type | Call or Put. |
| open_interest | Open interest on the contract. |
| volume | The trading volume. |
| theoretical_price | Theoretical value of the option. |
| last_trade_price | Last trade price of the option. |
| tick | Whether the last tick was up or down in price. |
| bid | Current bid price for the option. |
| bid_size | Bid size for the option. |
| ask | Current ask price for the option. |
| ask_size | Ask size for the option. |
| mark | The mid-price between the latest bid and ask. |
| open | The open price. |
| open_bid | The opening bid price for the option that day. |
| open_ask | The opening ask price for the option that day. |
| high | The high price. |
| bid_high | The highest bid price for the option that day. |
| ask_high | The highest ask price for the option that day. |
| low | The low price. |
| bid_low | The lowest bid price for the option that day. |
| ask_low | The lowest ask price for the option that day. |
| close | The close price. |
| close_size | The closing trade size for the option that day. |
| close_time | The time of the closing price for the option that day. |
| close_bid | The closing bid price for the option that day. |
| close_bid_size | The closing bid size for the option that day. |
| close_bid_time | The time of the bid closing price for the option that day. |
| close_ask | The closing ask price for the option that day. |
| close_ask_size | The closing ask size for the option that day. |
| close_ask_time | The time of the ask closing price for the option that day. |
| prev_close | |
| change | The change in the price of the option. |
| change_percent | Change, in normalizezd percentage points, of the option. |
| implied_volatility | Implied volatility of the option. |
| delta | Delta of the option. |
| gamma | Gamma of the option. |
| theta | Theta of the option. |
| vega | Vega of the option. |
| rho | Rho of the option. |
| exercise_style | The exercise style of the option, American or European. |