SELECT INQUI."País", COUNT(*) AS RESERVAS."Reservas$SUM", AVG(RESERVAS.Desde-RESERVAS."Fecha realizada") AS RESERVAS."Antelación media" FROM RESERVAS, INQUI WHERE RESERVAS.Desde >= ':1' AND RESERVAS.Desde <= ':2' AND RESERVAS.Agencia >= -1 AND INQUI."Código"=RESERVAS.Inquilino GROUP BY INQUI."País" ORDER BY INQUI."País"