SELECT
a.currency,
a.rate,
a.update_date,
b.rate,
b.update_date,
a.rate-b.rate AS trend,

(ROUND((a.rate-b.rate)/a.rate)+100,2) AS trend_pct FROM (SELECT * FROM currency_rate WHERE update_date = (SELECT MAX(update_date) FROM currency_rate)) a,

(SELECT * FROM currency_rate
WHERE update_date = (SELECT MAX(update_date) FROM currency_rate WHERE update_date < (SELECT MAX(update_date) FROM currency_rate))) b
WHERE a.currency_id = b.currency_id