To get the % useage of all available Open_cursors : 

Answer >

SELECT 'session_cached_cursors' parameter, LPAD(value, 5) value,
DECODE(value, 0, ' n/a', to_char(100 * used / value, '990') || '%' ) usage
FROM ( SELECT MAX(s.value) used
FROM v$statname n, v$sesstat s
WHERE
n.name = 'session cursor cache count' and
s.statistic# = n.statistic# ),
(SELECT value
FROM v$parameter
WHERE
name = 'session_cached_cursors' )
UNION ALL
SELECT 'open_cursors', LPAD(value, 5), to_char(100 * used / value, '990') || '%'
FROM
(SELECT MAX(sum(s.value)) used
FROM v$statname n, v$sesstat s
WHERE
n.name in ('opened cursors current', 'session cursor cache count') and s.statistic#=n.statistic#
GROUP BY
s.sid
),
(SELECT value
FROM v$parameter
WHERE
name = 'open_cursors' )
/