| prefix | string | No | Date_ | what to prefix the var name with | 
| time | timestamp/YYYY-MM-DD | No | current time in unix timestamp or YYYY-MM-DD format | what date/time to use | 
| start_year | string | No | current year | the first year in the dropdown, either
      year number, or relative to current year (+/- N) | 
| end_year | string | No | same as start_year | the last year in the dropdown, either
      year number, or relative to current year (+/- N) | 
| display_days | boolean | No | true | whether to display days or not | 
| display_months | boolean | No | true | whether to display months or not | 
| display_years | boolean | No | true | whether to display years or not | 
| month_format | string | No | %B | what format the month should be in (strftime) | 
| day_format | string | No | %02d | what format the day output should be in (sprintf) | 
| day_value_format | string | No | %d | what format the day value should be in (sprintf) | 
| year_as_text | boolean | No | false | whether or not to display the year as text | 
| reverse_years | boolean | No | false | display years in reverse order | 
| field_array | string | No | null | if a name is given, the select boxes will be drawn
      such that the results will be returned to PHP in the
      form of name[Day], name[Year], name[Month]. | 
| day_size | string | No | null | adds size attribute to select tag if given | 
| month_size | string | No | null | adds size attribute to select tag if given | 
| year_size | string | No | null | adds size attribute to select tag if given | 
| all_extra | string | No | null | adds extra attributes to all select/input tags if given | 
| day_extra | string | No | null | adds extra attributes to select/input tags if given | 
| month_extra | string | No | null | adds extra attributes to select/input tags if given | 
| year_extra | string | No | null | adds extra attributes to select/input tags if given | 
| field_order | string | No | MDY | the order in which to display the fields | 
| field_separator | string | No | \n | string printed between different fields | 
| month_value_format | string | No | %m | strftime format of the month values, default is
      %m for month numbers. | 
| year_empty | string | No | null | If supplied then the first element of the year's select-box has this
     value as it's label and "" as it's value. This is useful to make the
     select-box read "Please select a year" for example.
     Note that you can use values like "-MM-DD" as time-attribute to indicate
     an unselected year. | 
| month_empty | string | No | null | If supplied then the first element of the month's select-box has this
     value as it's label and "" as it's value. .
     Note that you can use values like "YYYY--DD" as time-attribute to indicate
     an unselected month. | 
| day_empty | string | No | null | If supplied then the first element of the day's select-box has this
     value as it's label and "" as it's value.
     Note that you can use values like "YYYY-MM-" as time-attribute to indicate
     an unselected day. |