Please read the following table in HTML format from a webpage and then answer the question in detail according to the table. Each table cell is defined by a <td> and a </td> tag. Each table row starts with a <tr> and ends with a </tr> tag. 'rowspan=m' and 'colspan=n' represents a cell spaning over 'm' rows and 'n' columns.

Webpage title:
Asit Sen (director)
Table title:
Hindi and Bengali
Table:
<table id='hittask' contenteditable='False'>
<tr> <th colspan=1 rowspan=1 > Year </th><th colspan=1 rowspan=1 > Film </th><th colspan=1 rowspan=1 > Language </th><th colspan=1 rowspan=1 > Notes </th></tr>
<tr> <td colspan=1 rowspan=1 > 1948 </td><td colspan=1 rowspan=1 > Biplabi </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > 1956 </td><td class="highlighted"  colspan=1 rowspan=1 > Chalachal </td><td class="highlighted"  colspan=1 rowspan=1 > Bengali </td><td colspan=1 rowspan=1 > Remade in Hindi as Safar in 1970. </td></tr>
<tr> <td colspan=1 rowspan=1 > 1959 </td><td colspan=1 rowspan=1 > Deep Jweley Jai </td><td colspan=1 rowspan=1 > Bengali </td><td colspan=1 rowspan=1 > The movie was remade in Hindi in 1969 as Khamoshi. </td></tr>
<tr> <td colspan=1 rowspan=1 > 1963 </td><td colspan=1 rowspan=1 > Uttar Falguni </td><td colspan=1 rowspan=1 > Bengali </td><td colspan=1 rowspan=1 > At the 11th National Film Awards, the film was awarded National Film Award for Best Feature Film in Bengali. </td></tr>
<tr> <td colspan=1 rowspan=1 > 1966 </td><td colspan=1 rowspan=1 > Mamta </td><td colspan=1 rowspan=1 > Hindi </td><td colspan=1 rowspan=1 > Remake of Uttar Falguni </td></tr>
<tr> <td colspan=1 rowspan=1 > 1968 </td><td colspan=1 rowspan=1 > Anokhi Raat </td><td colspan=1 rowspan=1 > Hindi </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 1969 </td><td colspan=1 rowspan=1 > Khamoshi </td><td colspan=1 rowspan=1 > Hindi </td><td colspan=1 rowspan=1 > Remake of Deep Jweley Jai </td></tr>
<tr> <td colspan=1 rowspan=1 > 1970 </td><td colspan=1 rowspan=1 > Maa Aur Mamta </td><td colspan=1 rowspan=1 > Hindi </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 1970 </td><td class="highlighted"  colspan=1 rowspan=1 > Safar </td><td class="highlighted"  colspan=1 rowspan=1 > Hindi </td><td class="highlighted"  colspan=1 rowspan=1 > Remake of 1956 Bengali film Chalachal. </td></tr>
<tr> <td colspan=1 rowspan=1 > 1970 </td><td colspan=1 rowspan=1 > Sharafat </td><td colspan=1 rowspan=1 > Hindi </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 1972 </td><td colspan=1 rowspan=1 > Anokha Daan </td><td colspan=1 rowspan=1 > Hindi </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 1972 </td><td colspan=1 rowspan=1 > Annadata </td><td colspan=1 rowspan=1 > Hindi </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 1975 </td><td colspan=1 rowspan=1 > Anari </td><td colspan=1 rowspan=1 > Hindi </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 1976 </td><td colspan=1 rowspan=1 > Bairaag </td><td colspan=1 rowspan=1 > Hindi </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 1982 </td><td colspan=1 rowspan=1 > Vakil Babu </td><td colspan=1 rowspan=1 > Hindi </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 1983 </td><td colspan=1 rowspan=1 > Mehndi </td><td colspan=1 rowspan=1 > Hindi </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 1984 </td><td colspan=1 rowspan=1 > Prarthana </td><td colspan=1 rowspan=1 > Bengali </td><td colspan=1 rowspan=1 >  </td></tr>
</table>
Question:
What has changed since 1966 for Asit Sen's films?
Answer:
Asit Sen made the Bengali film from 1956 to 1963 and started making the film in Hindi since 1966.