I've been underperforming you've been underperforming he's been underperforming we've been underperforming you've been underperforming they've been underperforming
I'd been underperforming you'd been underperforming he'd been underperforming we'd been underperforming you'd been underperforming they'd been underperforming
I'll be underperforming you'll be underperforming he'll be underperforming we'll be underperforming you'll be underperforming they'll be underperforming
Future perfect
I'll have underperformed you'll have underperformed he'll have underperformed we'll have underperformed you'll have underperformed they'll have underperformed
Future perfect continuous
I'll have been underperforming you'll have been underperforming he'll have been underperforming we'll have been underperforming you'll have been underperforming they'll have been underperforming
I'd be underperforming you'd be underperforming he'd be underperforming we'd be underperforming you'd be underperforming they'd be underperforming
Past
I'd have underperformed you'd have underperformed he'd have underperformed we'd have underperformed you'd have underperformed they'd have underperformed
Past continuous
I'd have been underperforming you'd have been underperforming he'd have been underperforming we'd have been underperforming you'd have been underperforming they'd have been underperforming