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Here are the anticipated prices for each option, taking into account projected user growth and various short-term discounts. There are two DC rows because the price for DC will be different (for a while) if we act before Feb 1, 2021 and get on a 'grandfathered' / advantaged plan to escape the 15-180% price hike coming then.
Our licensing spend will thus increase10x or 11x from its current $49,910 to
We are in for an 8x-13x price increase over the next 6 years 
Recommendations
The least disruptive move would be to move to Data Center, assuming we can afford it (the 'DC, after Feb 1, 2021' column). Moving early will lock in some discounts. Just be aware that DC is an annual subscription, not a perpetual license like Server, and that DC won't last forever (see blog post Betting on Atlassian DataCenter?). As happened with Server, DC is likely to undergo constant price increases to 'squeeze' larger customers onto Cloud.
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So our yearly pricing with Cloud would be:
| Year | Discount | Jira Tier | Jira Base Cost | Jira Cost | Confluence Tier | Confluence Base | Confluence Cost | Access Cost | Total |
|---|---|---|---|---|---|---|---|---|---|
| 2021 | 55% | 1801-2000 | $151,500 | $68,175 | 601-800 | $27,500 | $12,375 | $32,500 | $113,050 |
| 2022 | 40% | 2001-2250 | $169,000 | $101,400 | 801-1000 | $33,500 | $20,100 | $35,000 | $156,500 |
| 2023 | 20% | 2501-2750 | $204,000 | $163,200 | 1001-1200 | $39,500 | $31,600 | $40,000 | $234,800 |
| 2024 | 3001-3250 | $239,000 | $239,000 | 1001-1200 | $39,500 | $39,500 | $45,000 | $323,500 | |
| 2025 | 3501-3750 | $274,000 | $274,000 | 1201-1400 | $45,500 | $45,500 | $50,000 | $369,500 | |
| 2026 | 4001-4250 | $309,000 | $309,000 | 1201-1400 | $45,500 | $45,500 | $50,000 | $404,500 | |
| 2027 | 4501-4700 | $344,000 | $344,000 | 1201-1400 | $45,500 | $45,500 | $60,000 | $449,500 |
(Note: figures are from Atlassian's spreadsheet. Prices for Access diverge slightly from the website)
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