(Corrects day in para 1- should be Thursday instead of Wednesday)
Jan 9 (Reuters) - The Baltic Exchange's main sea freight index inched down on Thursday, falling for its 21st straight session, to an over eight-month low on lower demand across all vessels.
* The Baltic index, which tracks rates for capesize, panamax and supramax vessels that ferry dry bulk commodities, declined 1 point, or 0.1%, to 772 points, its lowest level since April 17, 2019.
* This is the smallest daily percentage fall since the index started its slide on Dec. 4.
* The capesize index fell 42 points, or 3.5%, to 1,155 - its lowest since May 7.
* Average daily earnings for capesizes, which typically transport 170,000-180,000 tonne cargoes including iron ore and coal, increased $179 to $9,199.
* The panamax index declined 18 points, or 2.2%, to 785 points, its lowest since Feb. 27.
* Average daily earnings for panamaxes, which usually carry coal or grain cargoes of about 60,000 tonnes to 70,000 tonnes, dipped $160 to $7,063.
* The supramax index fell 12 points to 581. (Reporting by Harshith Aranya in Bengaluru; Editing by Krishna Chandra Eluri)