One dYdX hour, two markets

dYdX's docs write funding as (premium ÷ 8) + interest, charged every hour. What does the ÷ 8 tell you?

• That dYdX pays funding every 8 hours
• That the premium is treated as an 8-hour rate and one eighth of it is charged each hour
• That you should divide the printed rate by 8 before using it

Which markets carry the 0.125 bps per hour interest by default?

• Cross markets
• Isolated markets
• Every market